diff --git a/LICENSE b/LICENSE
new file mode 100644
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,674 @@
+                    GNU GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+  The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+the GNU General Public License is intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.  We, the Free Software Foundation, use the
+GNU General Public License for most of our software; it applies also to
+any other work released this way by its authors.  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+  To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights.  Therefore, you have
+certain responsibilities if you distribute copies of the software, or if
+you modify it: responsibilities to respect the freedom of others.
+
+  For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received.  You must make sure that they, too, receive
+or can get the source code.  And you must show them these terms so they
+know their rights.
+
+  Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+  For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software.  For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+  Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the manufacturer
+can do so.  This is fundamentally incompatible with the aim of
+protecting users' freedom to change the software.  The systematic
+pattern of such abuse occurs in the area of products for individuals to
+use, which is precisely where it is most unacceptable.  Therefore, we
+have designed this version of the GPL to prohibit the practice for those
+products.  If such problems arise substantially in other domains, we
+stand ready to extend this provision to those domains in future versions
+of the GPL, as needed to protect the freedom of users.
+
+  Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish to
+avoid the special danger that patents applied to a free program could
+make it effectively proprietary.  To prevent this, the GPL assures that
+patents cannot be used to render the program non-free.
+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+                       TERMS AND CONDITIONS
+
+  0. Definitions.
+
+  "This License" refers to version 3 of the GNU General Public License.
+
+  "Copyright" also means copyright-like laws that apply to other kinds of
+works, such as semiconductor masks.
+
+  "The Program" refers to any copyrightable work licensed under this
+License.  Each licensee is addressed as "you".  "Licensees" and
+"recipients" may be individuals or organizations.
+
+  To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of an
+exact copy.  The resulting work is called a "modified version" of the
+earlier work or a work "based on" the earlier work.
+
+  A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+  To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy.  Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+  To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies.  Mere interaction with a user through
+a computer network, with no transfer of a copy, is not conveying.
+
+  An interactive user interface displays "Appropriate Legal Notices"
+to the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License.  If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+  1. Source Code.
+
+  The "source code" for a work means the preferred form of the work
+for making modifications to it.  "Object code" means any non-source
+form of a work.
+
+  A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+  The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form.  A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+  The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities.  However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work.  For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+  The Corresponding Source need not include anything that users
+can regenerate automatically from other parts of the Corresponding
+Source.
+
+  The Corresponding Source for a work in source code form is that
+same work.
+
+  2. Basic Permissions.
+
+  All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met.  This License explicitly affirms your unlimited
+permission to run the unmodified Program.  The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work.  This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+  You may make, run and propagate covered works that you do not
+convey, without conditions so long as your license otherwise remains
+in force.  You may convey covered works to others for the sole purpose
+of having them make modifications exclusively for you, or provide you
+with facilities for running those works, provided that you comply with
+the terms of this License in conveying all material for which you do
+not control copyright.  Those thus making or running the covered works
+for you must do so exclusively on your behalf, under your direction
+and control, on terms that prohibit them from making any copies of
+your copyrighted material outside their relationship with you.
+
+  Conveying under any other circumstances is permitted solely under
+the conditions stated below.  Sublicensing is not allowed; section 10
+makes it unnecessary.
+
+  3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+  No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+  When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such circumvention
+is effected by exercising rights under this License with respect to
+the covered work, and you disclaim any intention to limit operation or
+modification of the work as a means of enforcing, against the work's
+users, your or third parties' legal rights to forbid circumvention of
+technological measures.
+
+  4. Conveying Verbatim Copies.
+
+  You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+  You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+  5. Conveying Modified Source Versions.
+
+  You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these conditions:
+
+    a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.
+
+    b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under section
+    7.  This requirement modifies the requirement in section 4 to
+    "keep intact all notices".
+
+    c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy.  This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged.  This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.
+
+    d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.
+
+  A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit.  Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+  6. Conveying Non-Source Forms.
+
+  You may convey a covered work in object code form under the terms
+of sections 4 and 5, provided that you also convey the
+machine-readable Corresponding Source under the terms of this License,
+in one of these ways:
+
+    a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.
+
+    b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the
+    Corresponding Source from a network server at no charge.
+
+    c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source.  This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.
+
+    d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge.  You need not require recipients to copy the
+    Corresponding Source along with the object code.  If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source.  Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.
+
+    e) Convey the object code using peer-to-peer transmission, provided
+    you inform other peers where the object code and Corresponding
+    Source of the work are being offered to the general public at no
+    charge under subsection 6d.
+
+  A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+  A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal, family,
+or household purposes, or (2) anything designed or sold for incorporation
+into a dwelling.  In determining whether a product is a consumer product,
+doubtful cases shall be resolved in favor of coverage.  For a particular
+product received by a particular user, "normally used" refers to a
+typical or common use of that class of product, regardless of the status
+of the particular user or of the way in which the particular user
+actually uses, or expects or is expected to use, the product.  A product
+is a consumer product regardless of whether the product has substantial
+commercial, industrial or non-consumer uses, unless such uses represent
+the only significant mode of use of the product.
+
+  "Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to install
+and execute modified versions of a covered work in that User Product from
+a modified version of its Corresponding Source.  The information must
+suffice to ensure that the continued functioning of the modified object
+code is in no case prevented or interfered with solely because
+modification has been made.
+
+  If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information.  But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+  The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or updates
+for a work that has been modified or installed by the recipient, or for
+the User Product in which it has been modified or installed.  Access to a
+network may be denied when the modification itself materially and
+adversely affects the operation of the network or violates the rules and
+protocols for communication across the network.
+
+  Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+  7. Additional Terms.
+
+  "Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law.  If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+  When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it.  (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.)  You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+  Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders of
+that material) supplement the terms of this License with terms:
+
+    a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or
+
+    b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or
+
+    c) Prohibiting misrepresentation of the origin of that material, or
+    requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or
+
+    d) Limiting the use for publicity purposes of names of licensors or
+    authors of the material; or
+
+    e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or
+
+    f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions of
+    it) with contractual assumptions of liability to the recipient, for
+    any liability that these contractual assumptions directly impose on
+    those licensors and authors.
+
+  All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10.  If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term.  If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+  If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+  Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions;
+the above requirements apply either way.
+
+  8. Termination.
+
+  You may not propagate or modify a covered work except as expressly
+provided under this License.  Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+  However, if you cease all violation of this License, then your
+license from a particular copyright holder is reinstated (a)
+provisionally, unless and until the copyright holder explicitly and
+finally terminates your license, and (b) permanently, if the copyright
+holder fails to notify you of the violation by some reasonable means
+prior to 60 days after the cessation.
+
+  Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+  Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License.  If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+  9. Acceptance Not Required for Having Copies.
+
+  You are not required to accept this License in order to receive or
+run a copy of the Program.  Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance.  However,
+nothing other than this License grants you permission to propagate or
+modify any covered work.  These actions infringe copyright if you do
+not accept this License.  Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+  10. Automatic Licensing of Downstream Recipients.
+
+  Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License.  You are not responsible
+for enforcing compliance by third parties with this License.
+
+  An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations.  If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+  You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License.  For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+  11. Patents.
+
+  A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based.  The
+work thus licensed is called the contributor's "contributor version".
+
+  A contributor's "essential patent claims" are all patent claims
+owned or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version.  For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+  Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+  In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement).  To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+  If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients.  "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+  If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+  A patent license is "discriminatory" if it does not include within
+the scope of its coverage, prohibits the exercise of, or is
+conditioned on the non-exercise of one or more of the rights that are
+specifically granted under this License.  You may not convey a covered
+work if you are a party to an arrangement with a third party that is
+in the business of distributing software, under which you make payment
+to the third party based on the extent of your activity of conveying
+the work, and under which the third party grants, to any of the
+parties who would receive the covered work from you, a discriminatory
+patent license (a) in connection with copies of the covered work
+conveyed by you (or copies made from those copies), or (b) primarily
+for and in connection with specific products or compilations that
+contain the covered work, unless you entered into that arrangement,
+or that patent license was granted, prior to 28 March 2007.
+
+  Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+  12. No Surrender of Others' Freedom.
+
+  If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+  13. Use with the GNU Affero General Public License.
+
+  Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work.  The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+  14. Revised Versions of this License.
+
+  The Free Software Foundation may publish revised and/or new versions of
+the GNU General Public License from time to time.  Such new versions will
+be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+  Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU General
+Public License "or any later version" applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+  If the Program specifies that a proxy can decide which future
+versions of the GNU General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+  Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+  15. Disclaimer of Warranty.
+
+  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+    <program>  Copyright (C) <year>  <name of author>
+    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+<http://www.gnu.org/licenses/>.
+
+  The GNU General Public License does not permit incorporating your program
+into proprietary programs.  If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.  But first, please read
+<http://www.gnu.org/philosophy/why-not-lgpl.html>.
diff --git a/Language/SMTLib2/Pipe.hs b/Language/SMTLib2/Pipe.hs
new file mode 100644
--- /dev/null
+++ b/Language/SMTLib2/Pipe.hs
@@ -0,0 +1,13 @@
+module Language.SMTLib2.Pipe
+       (SMTPipe(),
+        createPipe,
+        createPipeFromHandle,
+        withPipe
+       ) where
+
+import Language.SMTLib2.Pipe.Internals
+import Language.SMTLib2 (SMT,withBackendExitCleanly)
+
+withPipe :: String -> [String] -> SMT SMTPipe a -> IO a
+withPipe solver args act
+  = withBackendExitCleanly (createPipe solver args) act
diff --git a/Language/SMTLib2/Pipe/Internals.hs b/Language/SMTLib2/Pipe/Internals.hs
new file mode 100644
--- /dev/null
+++ b/Language/SMTLib2/Pipe/Internals.hs
@@ -0,0 +1,1785 @@
+module Language.SMTLib2.Pipe.Internals where
+
+import Language.SMTLib2.Internals.Backend as B
+import Language.SMTLib2.Internals.Type --hiding (Constr,Field,Datatype)
+import qualified Language.SMTLib2.Internals.Type as Type
+import Language.SMTLib2.Internals.Type.Nat as Type
+import Language.SMTLib2.Internals.Type.List (List(..))
+import qualified Language.SMTLib2.Internals.Type.List as List
+import Language.SMTLib2.Internals.Expression hiding (Fun,Field,Var,QVar,LVar)
+import qualified Language.SMTLib2.Internals.Expression as Expr
+import qualified Language.SMTLib2.Internals.Proof as P
+import Language.SMTLib2.Strategy as Strat
+
+import qualified Data.Text as T
+import qualified Data.Text.Read as T
+import Data.Map (Map)
+import qualified Data.Map.Strict as Map
+import Data.Set (Set)
+import qualified Data.Set as Set
+import Data.IntMap (IntMap)
+import qualified Data.IntMap as IMap
+import Data.Proxy
+import Data.Typeable
+import Data.GADT.Compare
+import Data.GADT.Show
+#if !MIN_VERSION_base(4,8,0)
+import Data.Monoid
+#endif
+import Data.Foldable (foldlM)
+import Control.Monad.Except
+import Data.Traversable
+import qualified GHC.TypeLits as TL
+
+import System.Process
+import System.IO
+import qualified Data.ByteString as BS hiding (reverse)
+import qualified Data.ByteString.Char8 as BS8
+import Blaze.ByteString.Builder
+import Data.Attoparsec.ByteString
+
+import qualified Data.AttoLisp as L
+import qualified Data.Attoparsec.Number as L
+import Data.Ratio
+
+import Control.Monad.Identity
+import Control.Monad.Trans.Except
+import Control.Monad.State
+
+data PipeDatatype = forall a. IsDatatype a => PipeDatatype (Proxy a)
+
+data SMTPipe = SMTPipe { channelIn :: Handle
+                       , channelOut :: Handle
+                       , processHandle :: Maybe ProcessHandle
+                       , names :: Map String Int
+                       , vars :: Map T.Text RevVar
+                       , datatypes :: TypeRegistry T.Text T.Text T.Text
+                       , interpolationMode :: InterpolationMode }
+             deriving Typeable
+
+data RevVar = forall (t::Type). Var !(Repr t)
+            | forall (t::Type). QVar !(Repr t)
+            | forall (arg::[Type]) (t::Type). Fun !(List Repr arg) !(Repr t)
+            | forall (t::Type). FunArg !(Repr t)
+            | forall (t::Type). LVar !(Repr t)
+
+data InterpolationMode = Z3Interpolation [T.Text] [T.Text]
+                       | MathSATInterpolation
+
+type PipeVar = UntypedVar T.Text
+type PipeFun = UntypedFun T.Text
+
+newtype PipeClauseId = PipeClauseId T.Text deriving (Show,Eq,Ord,Typeable)
+
+type PipeProofNode = P.Proof L.Lisp (Expr SMTPipe) Int
+
+data PipeProof = PipeProof { proofNodes :: Map Int PipeProofNode
+                           , proofNode :: Int }
+
+instance Eq PipeProof where
+  (==) (PipeProof _ x) (PipeProof _ y) = x == y
+
+instance Ord PipeProof where
+  compare (PipeProof _ x) (PipeProof _ y) = compare x y
+
+instance Show PipeProof where
+  showsPrec p pr = showParen (p>10) $ showsPrec 0 (proofNode pr)
+
+instance GEq (Expr SMTPipe) where
+  geq (PipeExpr e1) (PipeExpr e2) = geq e1 e2
+
+instance GCompare (Expr SMTPipe) where
+  gcompare (PipeExpr e1) (PipeExpr e2) = gcompare e1 e2
+
+instance GShow (Expr SMTPipe) where
+  gshowsPrec = showsPrec
+
+instance GetType (Expr SMTPipe) where
+  getType (PipeExpr e) = getType e
+
+instance Backend SMTPipe where
+  type SMTMonad SMTPipe = IO
+  newtype Expr SMTPipe t = PipeExpr (Expression PipeVar PipeVar PipeFun PipeVar PipeVar (Expr SMTPipe) t) deriving (Show,Typeable)
+  type Var SMTPipe = PipeVar
+  type QVar SMTPipe = PipeVar
+  type Fun SMTPipe = PipeFun
+  type FunArg SMTPipe = PipeVar
+  type LVar SMTPipe = PipeVar
+  type ClauseId SMTPipe = PipeClauseId
+  type Model SMTPipe = AssignmentModel SMTPipe
+  type Proof SMTPipe = PipeProof
+  setOption opt b = do
+    putRequest b $ renderSetOption opt
+    return ((),b)
+  getInfo info b = do
+    putRequest b (renderGetInfo info)
+    resp <- parseResponse b
+    case info of
+      SMTSolverName -> case resp of
+        L.List [L.Symbol ":name",L.String name] -> return (T.unpack name,b)
+        _ -> error $ "Invalid response to 'get-info' query: "++show resp
+      SMTSolverVersion -> case resp of
+        L.List [L.Symbol ":version",L.String name] -> return (T.unpack name,b)
+        _ -> error $ "Invalid response to 'get-info' query: "++show resp
+  declareVar tp name b = do
+    let (sym,req,nnames) = renderDeclareVar (names b) tp name
+        nb = b { names = nnames
+               , vars = Map.insert sym (Var tp) (vars b) }
+    putRequest nb req
+    return (UntypedVar sym tp,nb)
+  createQVar tp name b = do
+    let name' = case name of
+          Just n -> n
+          Nothing -> "qv"
+        (name'',nb) = genName b name'
+    return (UntypedVar name'' tp,nb { vars = Map.insert name'' (QVar tp) (vars nb) })
+  createFunArg tp name b = do
+    let name' = case name of
+          Just n -> n
+          Nothing -> "fv"
+        (name'',nb) = genName b name'
+    return (UntypedVar name'' tp,nb { vars = Map.insert name'' (FunArg tp) (vars nb) })
+  defineVar name (PipeExpr expr) b = do
+    let tp = getType expr
+        (sym,req,nnames) = renderDefineVar (names b) tp name (exprToLisp (datatypes b) expr)
+        nb = b { names = nnames
+               , vars = Map.insert sym (Var tp) (vars b) }
+    putRequest nb req
+    return (UntypedVar sym tp,nb)
+  declareFun arg res name b = do
+    let (sym,req,nnames) = renderDeclareFun (names b) arg res name
+        nb = b { names = nnames
+               , vars = Map.insert sym (Fun arg res) (vars b) }
+    putRequest nb req
+    return (UntypedFun sym arg res,nb)
+  defineFun name arg body b = do
+    let argTp = runIdentity $ List.mapM (return . getType) arg
+        bodyTp = getType body
+        (name',req,nnames) = renderDefineFun (\(UntypedVar n _) -> L.Symbol n)
+                             (\(PipeExpr e) -> exprToLisp (datatypes b) e) (names b) name arg body
+        nb = b { names = nnames }
+    putRequest nb req
+    return (UntypedFun name' argTp bodyTp,nb)
+  assert (PipeExpr expr) b = do
+    putRequest b (L.List [L.Symbol "assert"
+                         ,exprToLisp (datatypes b) expr])
+    return ((),b)
+  assertId (PipeExpr expr) b = do
+    let (name,b1) = genName b "cl"
+    putRequest b1 (L.List [L.Symbol "assert"
+                          ,L.List [L.Symbol "!"
+                                  ,exprToLisp (datatypes b) expr
+                                  ,L.Symbol ":named"
+                                  ,L.Symbol name]])
+    return (PipeClauseId name,b1)
+  assertPartition (PipeExpr expr) part b = case interpolationMode b of
+    Z3Interpolation grpA grpB -> do
+      let (name,b1) = genName b "grp"
+      putRequest b1 (L.List [L.Symbol "assert"
+                          ,L.List [L.Symbol "!"
+                                  ,exprToLisp (datatypes b) expr
+                                  ,L.Symbol ":named"
+                                  ,L.Symbol name]])
+      return ((),b1 { interpolationMode = case part of
+                      PartitionA -> Z3Interpolation (name:grpA) grpB
+                      PartitionB -> Z3Interpolation grpA (name:grpB) })
+    MathSATInterpolation -> do
+      putRequest b (L.List [L.Symbol "assert"
+                           ,L.List [L.Symbol "!"
+                                  ,exprToLisp (datatypes b) expr
+                                  ,L.Symbol ":interpolation-group"
+                                  ,L.Symbol (case part of
+                                               PartitionA -> "partA"
+                                               PartitionB -> "partB")]])
+      return ((),b)
+  getUnsatCore b = do
+    putRequest b (L.List [L.Symbol "get-unsat-core"])
+    resp <- parseResponse b
+    case resp of
+      L.List names -> do
+        cids <- mapM (\name -> case name of
+                        L.Symbol name' -> return $ PipeClauseId name'
+                        _ -> error $ "smtlib2: Invalid clause when getting unsatisfiable core: "++show name
+                     ) names
+        return (cids,b)
+      _ -> error $ "smtlib2: Invalid response to query for unsatisfiable core: "++show resp
+  checkSat tactic limits b = do
+    putRequest b $ renderCheckSat tactic limits
+    res <- BS.hGetLine (channelOut b)
+    return (case res of
+              "sat" -> Sat
+              "sat\r" -> Sat
+              "unsat" -> Unsat
+              "unsat\r" -> Unsat
+              "unknown" -> Unknown
+              "unknown\r" -> Unknown
+              _ -> error $ "smtlib2: unknown check-sat response: "++show res,b)
+  getValue expr b = do
+    putRequest b (renderGetValue b expr)
+    l <- parseResponse b
+    return (parseGetValue b (getType expr) l,b)
+  getProof b = do
+    putRequest b renderGetProof
+    l <- parseResponse b
+    return (parseGetProof b l,b)
+  analyzeProof b pr = case Map.lookup (proofNode pr) (proofNodes pr) of
+    Just nd -> case nd of
+      P.Rule r args res -> P.Rule (show r) (fmap (\arg -> PipeProof (proofNodes pr) arg) args) res
+  push b = do
+    putRequest b (L.List [L.Symbol "push",L.Number $ L.I 1])
+    return ((),b)
+  pop b = do
+    putRequest b (L.List [L.Symbol "pop",L.Number $ L.I 1])
+    return ((),b)
+  getModel b = do
+    putRequest b (L.List [L.Symbol "get-model"])
+    mdl <- parseResponse b
+    case runExcept $ parseGetModel b mdl of
+      Right mdl' -> return (mdl',b)
+      Left err -> error $ "smtlib2: Unknown get-model response: "++err
+  simplify (PipeExpr expr) b = do
+    putRequest b (L.List [L.Symbol "simplify"
+                         ,exprToLisp (datatypes b) expr])
+    resp <- parseResponse b
+    case runExcept $ lispToExprTyped b (getType expr) resp of
+      Right res -> return (res,b)
+      Left err -> error $ "smtlib2: Unknown simplify response: "++show resp++" ["++err++"]"
+  toBackend expr b = return (PipeExpr expr,b)
+  fromBackend b (PipeExpr expr) = expr
+  interpolate b = do
+    case interpolationMode b of
+      Z3Interpolation grpA grpB -> do
+        putRequest b (L.List [L.Symbol "get-interpolant",getAnd grpA,getAnd grpB])
+      MathSATInterpolation -> do
+        putRequest b (L.List [L.Symbol "get-interpolant",L.List [L.Symbol "partA"]])
+    resp <- parseResponse b
+    case runExcept $ lispToExprTyped b BoolRepr resp of
+      Right res -> return (res,b)
+      Left err -> error $ "smtlib2: Unknown get-interpolant response: "++show resp++" ["++err++"]"
+    where
+      getAnd [] = L.Symbol "true"
+      getAnd [x] = L.Symbol x
+      getAnd xs = L.List $ (L.Symbol "and"):fmap L.Symbol xs
+  declareDatatypes coll b = do
+    let (req,nnames,nreg) = renderDeclareDatatype (names b) (datatypes b) coll
+        nb = b { names = nnames
+               , datatypes = nreg }
+    putRequest nb req
+    return ((),nb)
+  exit b = do
+    putRequest b (L.List [L.Symbol "exit"])
+    hClose (channelIn b)
+    hClose (channelOut b)
+    case processHandle b of
+      Nothing -> return ()
+      Just ph -> do
+        terminateProcess ph
+        _ <- waitForProcess ph
+        return ()
+    return ((),b)
+  comment msg b = do
+    hPutStrLn (channelIn b) ("; "++msg)
+    return ((),b)
+
+renderDeclareFun :: Map String Int -> List Repr arg -> Repr ret -> Maybe String
+                 -> (T.Text,L.Lisp,Map String Int)
+renderDeclareFun names args ret name
+  = (name'',L.List [L.Symbol "declare-fun"
+                   ,L.Symbol name''
+                   ,typeList args
+                   ,typeSymbol Set.empty ret],nnames)
+  where
+    name' = case name of
+              Just n -> n
+              Nothing -> "fun"
+    (name'',nnames) = genName' names name'
+
+renderDefineFun :: (GetType e,GetType fv)
+                => (forall t. fv t -> L.Lisp)
+                -> (forall t. e t -> L.Lisp)
+                -> Map String Int -> Maybe String
+                -> List fv arg
+                -> e ret
+                -> (T.Text,L.Lisp,Map String Int)
+renderDefineFun renderFV renderE names name args body
+  = (name'',L.List [L.Symbol "define-fun"
+                   ,L.Symbol name''
+                   ,L.List $ mkList renderFV args
+                   ,typeSymbol Set.empty (getType body)
+                   ,renderE body],nnames)
+  where
+    name' = case name of
+              Just n -> n
+              Nothing -> "fun"
+    (name'',nnames) = genName' names name'
+    mkList :: GetType fv => (forall t. fv t -> L.Lisp) -> List fv ts -> [L.Lisp]
+    mkList _ Nil = []
+    mkList renderFV (v ::: xs)
+      = (L.List [renderFV v,typeSymbol Set.empty (getType v)]):
+        mkList renderFV xs
+
+renderCheckSat :: Maybe Tactic -> CheckSatLimits -> L.Lisp
+renderCheckSat tactic limits
+  = L.List (if extendedCheckSat
+            then [L.Symbol "check-sat-using"
+                 ,case tactic of
+                    Just t -> tacticToLisp t
+                    Nothing -> L.Symbol "smt"]++
+                      (case limitTime limits of
+                         Just t -> [L.Symbol ":timeout"
+                                   ,L.Number (L.I t)]
+                         Nothing -> [])++
+                      (case limitMemory limits of
+                         Just m -> [L.Symbol ":max-memory"
+                                   ,L.Number (L.I m)]
+                         Nothing -> [])
+            else [L.Symbol "check-sat"])
+  where
+    extendedCheckSat = case tactic of
+      Just _ -> True
+      _ -> case limitTime limits of
+        Just _ -> True
+        _ -> case limitMemory limits of
+          Just _ -> True
+          _ -> False
+
+renderDeclareDatatype' :: Integer
+                       -> [(T.Text,[(T.Text,[(T.Text,L.Lisp)])])]
+                       -> L.Lisp
+renderDeclareDatatype' npar coll
+  = L.List [L.Symbol "declare-datatypes"
+           ,case npar of
+              0 -> L.Symbol "()"
+              _ -> L.List [L.Symbol $ T.pack $ "a"++show i
+                          | i <- [0..npar-1]]
+           ,L.List [ L.List ((L.Symbol name):
+                             [L.List ((L.Symbol con):
+                                      [ L.List [L.Symbol field
+                                               ,tp]
+                                      | (field,tp) <- fields ])
+                             | (con,fields) <- cons ])
+                   | (name,cons) <- coll]]
+
+renderDeclareDatatype :: Map String Int -> TypeRegistry T.Text T.Text T.Text -> [AnyDatatype]
+                      -> (L.Lisp,Map String Int,TypeRegistry T.Text T.Text T.Text)
+renderDeclareDatatype names reg dts
+  = (renderDeclareDatatype' (case dts of
+                               AnyDatatype dt : _ -> naturalToInteger (parameters dt)
+                               [] -> 0)
+      str,nnames,nreg)
+  where
+    ((nnames,nreg),str) = mapAccumL mkDt (names,reg) dts
+    mkDt (names,reg) dt'@(AnyDatatype dt)
+      = let (name,names1) = genName' names (datatypeName dt)
+            reg1 = reg { allDatatypes = Map.insert name dt' (allDatatypes reg)
+                       , revDatatypes = Map.insert dt' name (revDatatypes reg) }
+            (cons,(names2,reg2)) = runState (List.toList (mkCon dt)
+                                             (constructors dt)) (names1,reg1)
+        in ((names2,reg2),(name,cons))
+    mkCon dt con = do
+      (names,reg) <- get
+      let (name,names1) = genName' names (constrName con)
+          reg1 = reg { allConstructors = Map.insert name (AnyConstr dt con) (allConstructors reg)
+                     , revConstructors = Map.insert (AnyConstr dt con) name (revConstructors reg) }
+      put (names1,reg1)
+      fs <- List.toList (mkField dt) (fields con)
+      return (name,fs)
+    mkField dt field = do
+      (names,reg) <- get
+      let (name,names1) = genName' names (fieldName field)
+          reg1 = reg { allFields = Map.insert name (AnyField dt field) (allFields reg)
+                     , revFields = Map.insert (AnyField dt field) name (revFields reg) }
+      put (names1,reg1)
+      return (name,typeSymbol allTypes (fieldType field))
+
+    allParameters :: (forall n. Natural n -> a) -> a
+    allParameters f = case dts of
+      AnyDatatype dt : dts'
+        | all (\(AnyDatatype dt') -> case geq (parameters dt') (parameters dt) of
+                  Just Refl -> True
+                  Nothing -> False) dts' -> f (parameters dt)
+      _ -> error "Not all datatypes in a cycle share the same parameters."
+
+    isRecType :: IsDatatype dt => Datatype dt -> Bool
+    isRecType dt = Set.member (datatypeName dt) allTypes
+    
+    allTypes :: Set String
+    allTypes = Set.fromList [ datatypeName dt
+                            | AnyDatatype dt <- dts ]
+    
+renderSetOption :: SMTOption -> L.Lisp
+renderSetOption (SMTLogic name) = L.List [L.Symbol "set-logic",L.Symbol $ T.pack name]
+renderSetOption opt
+  = L.List $ [L.Symbol "set-option"]++
+    (case opt of
+        PrintSuccess v -> [L.Symbol ":print-success"
+                          ,L.Symbol $ if v then "true" else "false"]
+        ProduceModels v -> [L.Symbol ":produce-models"
+                           ,L.Symbol $ if v then "true" else "false"]
+        B.ProduceProofs v -> [L.Symbol ":produce-proofs"
+                             ,L.Symbol $ if v then "true" else "false"]
+        B.ProduceUnsatCores v -> [L.Symbol ":produce-unsat-cores"
+                                 ,L.Symbol $ if v then "true" else "false"]
+        ProduceInterpolants v -> [L.Symbol ":produce-interpolants"
+                                 ,L.Symbol $ if v then "true" else "false"])
+
+renderGetInfo :: SMTInfo i -> L.Lisp
+renderGetInfo SMTSolverName
+  = L.List [L.Symbol "get-info"
+           ,L.Symbol ":name"]
+renderGetInfo SMTSolverVersion
+  = L.List [L.Symbol "get-info"
+           ,L.Symbol ":version"]
+
+renderDeclareVar :: Map String Int -> Repr tp -> Maybe String
+                 -> (T.Text,L.Lisp,Map String Int)
+renderDeclareVar names tp name
+  = (name'',L.List [L.Symbol "declare-fun"
+                   ,L.Symbol name''
+                   ,L.Symbol "()"
+                   ,typeSymbol Set.empty tp
+                   ],nnames)
+  where
+    name' = case name of
+              Just n -> n
+              Nothing -> "var"
+    (name'',nnames) = genName' names name'
+
+renderDefineVar :: Map String Int -> Repr t -> Maybe String -> L.Lisp
+                -> (T.Text,L.Lisp,Map String Int)
+renderDefineVar names tp name lexpr
+  = (name'',
+     L.List [L.Symbol "define-fun"
+            ,L.Symbol name''
+            ,L.Symbol "()"
+            ,typeSymbol Set.empty tp
+            ,lexpr],
+     nnames)
+  where
+    name' = case name of
+              Just n -> n
+              Nothing -> "var"
+    (name'',nnames) = genName' names name'
+
+renderGetValue :: SMTPipe -> Expr SMTPipe t -> L.Lisp
+renderGetValue b (PipeExpr e) = L.List [L.Symbol "get-value"
+                                       ,L.List [exprToLisp (datatypes b) e]]
+
+parseGetValue :: SMTPipe -> Repr t -> L.Lisp -> Value t
+parseGetValue b repr (L.List [L.List [_,val]])
+  = case runExcept $ lispToValue b (Just $ Sort repr) val of
+  Right (AnyValue v) -> case geq repr (valueType v) of
+    Just Refl -> v
+    Nothing -> error $ "smtlib2: Wrong type of returned value."
+  Left err -> error $ "smtlib2: Failed to parse get-value entry: "++show val++" ["++err++"]"
+parseGetValue _ _ expr = error $ "smtlib2: Failed to parse get-value result: "++show expr
+
+renderGetProof :: L.Lisp
+renderGetProof = L.List [L.Symbol "get-proof"]
+
+parseGetProof :: SMTPipe -> L.Lisp -> PipeProof
+parseGetProof b resp = case runExcept $ parseProof b Map.empty Map.empty Map.empty proof of
+  Right res -> res
+  Left err -> error $ "smtlib2: Failed to parse proof: "++show resp++" ["++err++"]"
+  where
+    proof = case resp of
+      L.List items -> case findProof items of
+        Nothing -> resp
+        Just p -> p
+      _ -> resp
+    findProof [] = Nothing
+    findProof ((L.List [L.Symbol "proof",p]):_) = Just p
+    findProof (x:xs) = findProof xs
+
+parseProof :: SMTPipe
+           -> Map T.Text (Expr SMTPipe BoolType)
+           -> Map T.Text Int
+           -> Map Int PipeProofNode
+           -> L.Lisp
+           -> LispParse PipeProof
+parseProof pipe exprs proofs nodes l = case l of
+  L.List [L.Symbol "let",L.List defs,body] -> do
+    (nexprs,nproofs,nnodes)
+      <- foldlM (\(exprs,proofs,nodes) def
+                 -> case def of
+                    L.List [L.Symbol name,def'] -> do
+                      res <- parseDef exprs proofs nodes def'
+                      case res of
+                        Left expr -> return (Map.insert name expr exprs,proofs,nodes)
+                        Right (proof,nnodes)
+                          -> return (exprs,Map.insert name proof proofs,nnodes)
+                ) (exprs,proofs,nodes) defs
+    parseProof pipe nexprs nproofs nnodes body
+  _ -> do
+    (res,nnodes) <- parseDefProof exprs proofs nodes l
+    return (PipeProof nnodes res)
+  where
+    exprParser = pipeParser pipe
+    exprParser' exprs = exprParser { parseRecursive = \_ -> parseDefExpr' exprs
+                                   }
+    parseDefExpr' :: Map T.Text (Expr SMTPipe BoolType) -> Maybe Sort -> L.Lisp
+                  -> (forall tp. Expr SMTPipe tp -> LispParse a)
+                  -> LispParse a
+    parseDefExpr' exprs srt l@(L.Symbol name) res = case Map.lookup name exprs of
+      Just def -> res def
+      Nothing -> lispToExprWith (exprParser' exprs) srt l $
+                 \e -> res (PipeExpr e)
+    parseDefExpr' exprs srt l res = lispToExprWith (exprParser' exprs) srt l
+                                    (res.PipeExpr)
+    parseDefExpr :: Map T.Text (Expr SMTPipe BoolType) -> L.Lisp
+                 -> LispParse (Expr SMTPipe BoolType)
+    parseDefExpr exprs l = parseDefExpr' exprs (Just $ Sort BoolRepr) l $
+                           \e -> case getType e of
+                             BoolRepr -> return e
+                             _ -> throwError "let expression in proof is not bool"
+    parseDefProof exprs proofs nodes (L.List (rule:args)) = do
+      (args',res,nnodes) <- parseArgs nodes args
+      let sz = Map.size nnodes
+      return (sz,Map.insert sz (P.Rule rule args' res) nnodes)
+      where
+        parseArgs nodes [x] = case x of
+          L.List [L.Symbol "~",lhs,rhs] -> do
+            lhs' <- parseDefExpr exprs lhs
+            rhs' <- parseDefExpr exprs rhs
+            return ([],P.EquivSat lhs' rhs',nodes)
+          _ -> do
+            e <- parseDefExpr exprs x
+            return ([],P.ProofExpr e,nodes)
+        parseArgs nodes (x:xs) = do
+          (nd,nodes1) <- parseDefProof exprs proofs nodes x
+          (nds,res,nodes2) <- parseArgs nodes1 xs
+          return (nd:nds,res,nodes2)
+    parseDefProof exprs proofs nodes (L.Symbol sym) = case Map.lookup sym proofs of
+      Just pr -> return (pr,nodes)
+    parseDef exprs proofs nodes l
+      = (fmap Left $ parseDefExpr exprs l) `catchError`
+        (\_ -> fmap Right $ parseDefProof exprs proofs nodes l)
+
+parseGetModel :: SMTPipe -> L.Lisp -> LispParse (Model SMTPipe)
+parseGetModel b (L.List ((L.Symbol "model"):mdl)) = do
+  nb <- foldlM adapt b mdl
+  assign <- mapM (parseAssignment nb) mdl
+  return $ AssignmentModel assign
+  where
+    adapt b (L.List [L.Symbol "define-fun",L.Symbol fname,L.List args,rtp,body])
+      = case args of
+      [] -> do
+        srt@(Sort tp) <- lispToSort (pipeParser b) rtp
+        return $ b { vars = Map.insert fname (Var tp) (vars b) }
+      _ -> do
+        srt@(Sort tp) <- lispToSort (pipeParser b) rtp
+        withFunList b args $
+          \b' tps args'
+           -> return $ b { vars = Map.insert fname (Fun tps tp) (vars b) }
+    parseAssignment b (L.List [L.Symbol "define-fun",L.Symbol fname,L.List args,rtp,body])
+      = case args of
+        [] -> do
+          srt@(Sort tp) <- lispToSort (pipeParser b) rtp
+          expr <- lispToExprTyped b tp body
+          return $ VarAssignment (UntypedVar fname tp) expr
+        _ -> do
+          srt@(Sort tp) <- lispToSort (pipeParser b) rtp
+          withFunList b args $
+            \b' tps args' -> do
+              body' <- lispToExprTyped b' tp body
+              return $ FunAssignment (UntypedFun fname tps tp) args' body'
+    parseAssignment _ lsp = throwE $ "Invalid model entry: "++show lsp
+    withFunList :: SMTPipe -> [L.Lisp]
+                -> (forall arg. SMTPipe -> List Repr arg -> List PipeVar arg -> LispParse a) -> LispParse a
+    withFunList b [] f = f b Nil Nil
+    withFunList b ((L.List [L.Symbol v,tp]):ls) f = do
+      Sort tp <- lispToSort (pipeParser b) tp
+      withFunList (b { vars = Map.insert v (FunArg tp) (vars b) }) ls $
+        \b' tps args -> f b' (tp ::: tps) ((UntypedVar v tp) ::: args)
+    withFunList _ lsp _ = throwE $ "Invalid fun args: "++show lsp
+parseGetModel _ lsp = throwE $ "Invalid model: "++show lsp
+
+data Sort = forall (t :: Type). Sort (Repr t)
+data Sorts = forall (t :: [Type]). Sorts (List Repr t)
+
+data ParsedFunction fun
+  = ParsedFunction { argumentTypeRequired :: Integer -> Bool
+                   , getParsedFunction :: [Maybe Sort] -> LispParse (AnyFunction fun)
+                   }
+
+data AnyExpr e = forall (t :: Type). AnyExpr (e t)
+
+instance GShow e => Show (AnyExpr e) where
+  showsPrec p (AnyExpr x) = gshowsPrec p x
+
+data LispParser (v :: Type -> *) (qv :: Type -> *) (fun :: ([Type],Type) -> *) (fv :: Type -> *) (lv :: Type -> *) (e :: Type -> *)
+  = LispParser { parseFunction :: forall a. Maybe Sort -> T.Text
+                               -> (forall args res. fun '(args,res) -> LispParse a)
+                               -> (forall args res. (IsDatatype res) => Type.Datatype res -> Type.Constr res args -> LispParse a) -- constructor
+                               -> (forall args res. (IsDatatype res) => Type.Datatype res -> Type.Constr res args -> LispParse a) -- constructor test
+                               -> (forall t args res. (IsDatatype t) => Type.Datatype t -> Type.Field t res -> LispParse a)
+                               -> LispParse a
+               , parseDatatype :: forall a. T.Text
+                               -> (forall dt. IsDatatype dt
+                                   => Type.Datatype dt -> LispParse a)
+                               -> LispParse a
+               , parseVar :: forall a. Maybe Sort -> T.Text
+                          -> (forall t. v t -> LispParse a)
+                          -> (forall t. qv t -> LispParse a)
+                          -> (forall t. fv t -> LispParse a)
+                          -> (forall t. lv t -> LispParse a)
+                          -> LispParse a
+               , parseRecursive :: forall a. LispParser v qv fun fv lv e
+                                -> Maybe Sort -> L.Lisp
+                                -> (forall t. e t -> LispParse a)
+                                -> LispParse a
+               , registerQVar :: forall (t :: Type). T.Text -> Repr t
+                              -> (qv t,LispParser v qv fun fv lv e)
+               , registerLetVar :: forall (t :: Type). T.Text -> Repr t
+                                -> (lv t,LispParser v qv fun fv lv e)
+               }
+
+type LispParse = Except String
+
+-- | Spawn a new SMT solver process and create a pipe to communicate with it.
+createPipe :: String -- ^ Path to the binary of the SMT solver
+         -> [String] -- ^ Command line arguments to be passed to the SMT solver
+         -> IO SMTPipe
+createPipe solver args = do
+  let cmd = (proc solver args) { std_in = CreatePipe
+                               , std_out = CreatePipe
+                               , std_err = Inherit
+                               , close_fds = False }
+  (Just hin,Just hout,_,handle) <- createProcess cmd
+  let p0 = SMTPipe { channelIn = hin
+                   , channelOut = hout
+                   , processHandle = Just handle
+                   , names = Map.empty
+                   , vars = Map.empty
+                   , datatypes = emptyTypeRegistry
+                   , interpolationMode = MathSATInterpolation }
+  putRequest p0 (L.List [L.Symbol "get-info"
+                        ,L.Symbol ":name"])
+  resp <- parseResponse p0
+  case resp of
+    L.List [L.Symbol ":name",L.String name] -> case name of
+      "Z3" -> return $ p0 { interpolationMode = Z3Interpolation [] [] }
+      _ -> return p0
+    _ -> return p0
+
+-- | Create a SMT pipe by giving the input and output handle.
+createPipeFromHandle :: Handle -- ^ Input handle
+                     -> Handle -- ^ Output handle
+                     -> IO SMTPipe
+createPipeFromHandle hin hout = do
+  return SMTPipe { channelIn = hin
+                 , channelOut = hout
+                 , processHandle = Nothing
+                 , names = Map.empty
+                 , vars = Map.empty
+                 , datatypes = emptyTypeRegistry
+                 , interpolationMode = MathSATInterpolation }
+
+lispToExprUntyped :: SMTPipe -> L.Lisp
+                  -> (forall (t::Type). Expr SMTPipe t -> LispParse a)
+                  -> LispParse a
+lispToExprUntyped st l res = lispToExprWith (pipeParser st) Nothing l $
+                             \e -> res (PipeExpr e)
+
+lispToExprTyped :: SMTPipe -> Repr t -> L.Lisp -> LispParse (Expr SMTPipe t)
+lispToExprTyped st tp l = lispToExprWith (pipeParser st) (Just (Sort tp)) l $
+                          \e -> case geq tp (getType e) of
+                          Just Refl -> return (PipeExpr e)
+                          Nothing -> throwE $ show l++" has type "++show (getType e)++", but "++show tp++" was expected."
+
+pipeParser :: SMTPipe
+           -> LispParser PipeVar PipeVar PipeFun PipeVar PipeVar (Expr SMTPipe)
+pipeParser st = parse
+  where
+  parse = LispParser { parseFunction = \srt name fun con test field
+                                       -> case T.stripPrefix "is-" name of
+                                       Just con -> case Map.lookup name (allConstructors $ datatypes st) of
+                                         Just (AnyConstr dt con) -> test dt con
+                                         _ -> throwE $ "Unknown constructor: "++show name
+                                       Nothing -> case Map.lookup name (allConstructors $ datatypes st) of
+                                         Just (AnyConstr dt c) -> con dt c
+                                         Nothing -> case Map.lookup name (allFields $ datatypes st) of
+                                           Just (AnyField dt f) -> field dt f
+                                           Nothing -> case Map.lookup name (vars st) of
+                                             Just (Fun arg tp)
+                                               -> fun (UntypedFun name arg tp)
+                                             _ -> throwE $ "Unknown symbol "++show name
+                     , parseDatatype = \name res -> case Map.lookup name (allDatatypes $ datatypes st) of
+                                         Just (AnyDatatype p) -> res p
+                                         _ -> throwE $ "Unknown datatype "++show name
+                     , parseVar = \srt name v qv fv lv -> case Map.lookup name (vars st) of
+                                    Just (Var tp)
+                                      -> v (UntypedVar name tp)
+                                    Just (QVar tp)
+                                      -> qv (UntypedVar name tp)
+                                    Just (FunArg tp)
+                                      -> fv (UntypedVar name tp)
+                                    Just (LVar tp)
+                                      -> lv (UntypedVar name tp)
+                                    _ -> throwE $ "Unknown variable "++show name
+                     , parseRecursive = \parse srt l res -> lispToExprWith parse srt l $
+                                                            \e -> res (PipeExpr e)
+                     , registerQVar = \name tp
+                                      -> (UntypedVar name tp,
+                                          pipeParser (st { vars = Map.insert name (QVar tp)
+                                                                  (vars st) }))
+                     , registerLetVar = \name tp
+                                        -> (UntypedVar name tp,
+                                            pipeParser (st { vars = Map.insert name (LVar tp)
+                                                                    (vars st) }))
+                     }
+
+lispToExprWith :: (GShow fun,GShow e,GetFunType fun,GetType e)
+               => LispParser v qv fun fv lv e
+               -> Maybe Sort
+               -> L.Lisp
+               -> (forall (t :: Type).
+                   Expression v qv fun fv lv e t
+                   -> LispParse a)
+               -> LispParse a
+lispToExprWith p hint (runExcept . lispToConstant -> Right (AnyValue val)) res
+  = res (Const val)
+lispToExprWith p hint (L.Symbol sym) res
+  = parseVar p hint sym (res . Expr.Var) (res . Expr.QVar) (res . Expr.FVar) (res . Expr.LVar) `catchError`
+    (\_ -> do
+        parsed <- lispToFunction p hint (L.Symbol sym)
+        AnyFunction f <- getParsedFunction parsed []
+        case getFunType f of
+          (Nil,_) -> res $ App f Nil
+          _ -> throwError $ "Arguments expected for function "++show sym)
+lispToExprWith p hint (L.List [L.Symbol "_",L.Symbol "as-array",fsym]) res = do
+  parsed <- lispToFunction p el_hint fsym
+  AnyFunction fun <- getParsedFunction parsed idx_hint
+  res (AsArray fun)
+  where
+    (idx_hint,el_hint) = case hint of
+      Nothing -> ([],Nothing)
+      Just (Sort tp) -> case tp of
+        ArrayRepr args el
+          -> (runIdentity $ List.toList (\t -> return (Just $ Sort t)) args,
+              Just $ Sort el)
+lispToExprWith p hint (L.List [L.Symbol "forall",L.List args,body]) res
+  = mkQuant p args $
+    \np args' -> parseRecursive np np (Just (Sort BoolRepr)) body $
+                 \body' -> case getType body' of
+                 BoolRepr -> res (Quantification Forall args' body')
+lispToExprWith p hint (L.List [L.Symbol "exists",L.List args,body]) res
+  = mkQuant p args $
+    \np args' -> parseRecursive np np (Just (Sort BoolRepr)) body $
+                 \body' -> case getType body' of
+                 BoolRepr -> res (Quantification Exists args' body')
+lispToExprWith p hint (L.List [L.Symbol "let",L.List args,body]) res
+  = mkLet p args $
+    \np args' -> parseRecursive np np hint body $
+                 \body' -> res (Let args' body')
+lispToExprWith p hint (L.List [L.Symbol "as",expr,tp]) res = do
+  srt <- lispToSort p tp
+  lispToExprWith p (Just srt) expr res
+lispToExprWith p hint (L.List (fun:args)) res = do
+  parsed <- lispToFunction p hint fun
+  args' <- matchList (argumentTypeRequired parsed) 0 args
+  let hints = fmap (\arg -> case arg of
+                      Left _ -> Nothing
+                      Right (AnyExpr e) -> Just $ Sort (getType e)
+                   ) args'
+  AnyFunction fun' <- getParsedFunction parsed hints
+  let (argTps,ret) = getFunType fun'
+  args'' <- catchE (makeList p argTps args') $
+            \err -> throwE $ "While parsing arguments of function: "++
+                    show fun'++": "++err
+  res $ App fun' args''
+  where
+    matchList _ _ [] = return []
+    matchList f i (e:es) = if f i
+                           then parseRecursive p p Nothing e
+                                (\e' -> do
+                                     rest <- matchList f (i+1) es
+                                     return $ (Right (AnyExpr e')):rest)
+                           else do
+                             rest <- matchList f (i+1) es
+                             return $ (Left e):rest
+    makeList :: (GShow e,GetType e) => LispParser v qv fun fv lv e
+             -> List Repr arg -> [Either L.Lisp (AnyExpr e)] -> LispParse (List e arg)
+    makeList _ Nil [] = return Nil
+    makeList _ Nil _  = throwE $ "Too many arguments to function."
+    makeList p (tp ::: args) (e:es) = case e of
+      Right (AnyExpr e') -> do
+        r <- case geq tp (getType e') of
+           Just Refl -> return e'
+           Nothing -> throwE $ "Argument "++gshowsPrec 11 e' ""++" has wrong type."
+        rs <- makeList p args es
+        return (r ::: rs)
+      Left l -> parseRecursive p p (Just $ Sort tp) l $
+                \e' -> do
+                  r <- case geq tp (getType e') of
+                     Just Refl -> return e'
+                     Nothing -> throwE $ "Argument "++gshowsPrec 11 e' ""++" has wrong type."
+                  rs <- makeList p args es
+                  return (r ::: rs)
+    makeList _ (_ ::: _) [] = throwE $ "Not enough arguments to function."
+lispToExprWith _ _ lsp _ = throwE $ "Invalid SMT expression: "++show lsp
+
+mkQuant :: LispParser v qv fun fv lv e -> [L.Lisp]
+        -> (forall arg. LispParser v qv fun fv lv e -> List qv arg -> LispParse a)
+        -> LispParse a
+mkQuant p [] f = f p Nil
+mkQuant p ((L.List [L.Symbol name,sort]):args) f = do
+  Sort srt <- lispToSort p sort
+  let (qvar,np) = registerQVar p name srt
+  mkQuant np args $ \p args -> f p (qvar ::: args)
+mkQuant _ lsp _ = throwE $ "Invalid forall/exists parameter: "++show lsp
+
+mkLet :: GetType e
+      => LispParser v qv fun fv lv e -> [L.Lisp]
+         -> (forall arg. LispParser v qv fun fv lv e
+             -> List (LetBinding lv e) arg -> LispParse a)
+         -> LispParse a
+mkLet p [] f = f p Nil
+mkLet p ((L.List [L.Symbol name,expr]):args) f
+  = parseRecursive p p Nothing expr $
+    \expr' -> do
+      let (lvar,np) = registerLetVar p name (getType expr')
+      mkLet np args $ \p args -> f p ((LetBinding lvar expr') ::: args)
+mkLet _ lsp _ = throwE $ "Invalid let parameter: "++show lsp
+
+withEq :: Repr t -> [b]
+       -> (forall n. Natural n -> List Repr (AllEq t n) -> a)
+       -> a
+withEq tp [] f = f Zero Nil
+withEq tp (_:xs) f = withEq tp xs $
+                     \n args -> f (Succ n) (tp ::: args)
+                                             
+lispToFunction :: LispParser v qv fun fv lv e
+               -> Maybe Sort -> L.Lisp -> LispParse (ParsedFunction fun)
+lispToFunction _ _ (L.Symbol "=")
+  = return $ ParsedFunction (==0)
+    (\args -> case args of
+       Just (Sort tp):_ -> withEq tp args $
+                           \n args
+                           -> return $ AnyFunction (Eq tp n)
+       _ -> throwE $ "Cannot derive type of = parameters.")
+lispToFunction _ _ (L.Symbol "distinct")
+  = return $ ParsedFunction (==0)
+    (\args -> case args of
+       Just (Sort tp):_ -> withEq tp args $
+                           \n args' -> return $ AnyFunction (Distinct tp n)
+       _ -> throwE $ "Cannot derive type of \"distinct\" parameters.")
+lispToFunction rf sort (L.List [L.Symbol "_",L.Symbol "map",sym]) = do
+  f <- lispToFunction rf sort' sym
+  let reqList 0 = case idx' of
+        Nothing -> True
+        Just _ -> argumentTypeRequired f 0
+      reqList n = argumentTypeRequired f n
+      fun args = do
+        Sorts pidx <- case idx' of
+          Just srts -> return srts
+          Nothing -> case args of
+            Just srt:_ -> case asArraySort srt of
+              Just (idx,_) -> return idx
+              Nothing -> throwE $ "Could not derive type of the array index in map function."
+            _ -> throwE $ "Could not derive type of the array index in map function."
+        argSorts <- mapM (\prx -> case prx of
+                            Nothing -> return Nothing
+                            Just srt -> do
+                              (_,elsrt) <- case asArraySort srt of
+                                Just srt' -> return srt'
+                                Nothing -> throwE $ "Argument to map function isn't an array."
+                              return (Just elsrt)
+                         ) args
+        fun' <- getParsedFunction f argSorts
+        return $ mkMap pidx fun'
+  return (ParsedFunction reqList fun)
+  where
+    (sort',idx') = case sort of
+      Just (Sort tp) -> case tp of
+        ArrayRepr idx el
+          -> (Just (Sort el),
+              Just (Sorts idx))
+        _ -> (Nothing,Nothing)
+      _ -> (Nothing,Nothing)
+lispToFunction _ _ (L.Symbol ">=") = lispToOrdFunction Ge
+lispToFunction _ _ (L.Symbol ">") = lispToOrdFunction Gt
+lispToFunction _ _ (L.Symbol "<=") = lispToOrdFunction Le
+lispToFunction _ _ (L.Symbol "<") = lispToOrdFunction Lt
+lispToFunction _ sort (L.Symbol "+") = lispToArithFunction sort Plus
+lispToFunction _ sort (L.Symbol "*") = lispToArithFunction sort Mult
+lispToFunction _ sort (L.Symbol "-") = lispToArithFunction sort Minus
+lispToFunction _ _ (L.Symbol "div") = return $ ParsedFunction (const False)
+                                      (\_ -> return $ AnyFunction (ArithIntBin Div))
+lispToFunction _ _ (L.Symbol "mod") = return $ ParsedFunction (const False)
+                                      (\_ -> return $ AnyFunction (ArithIntBin Mod))
+lispToFunction _ _ (L.Symbol "rem") = return $ ParsedFunction (const False)
+                                      (\_ -> return $ AnyFunction (ArithIntBin Rem))
+lispToFunction _ _ (L.Symbol "/") = return $ ParsedFunction (const False)
+                                    (\_ -> return $ AnyFunction Divide)
+lispToFunction _ sort (L.Symbol "abs") = case sort of
+  Just (Sort tp) -> case tp of
+    IntRepr -> return $ ParsedFunction (const False) (\_ -> return $ AnyFunction (Abs NumInt))
+    RealRepr -> return $ ParsedFunction (const False) (\_ -> return $ AnyFunction (Abs NumReal))
+    exp -> throwE $ "abs function can't have type "++show exp
+  Nothing -> return $ ParsedFunction (==0) $
+             \args -> case args of
+                [Just (Sort tp)] -> case tp of
+                  IntRepr -> return $ AnyFunction (Abs NumInt)
+                  RealRepr -> return $ AnyFunction (Abs NumReal)
+                  srt -> throwE $ "abs can't take argument of type "++show srt
+                _ -> throwE $ "abs function takes exactly one argument."
+lispToFunction _ _ (L.Symbol "not")
+  = return $ ParsedFunction (const False) (\_ -> return $ AnyFunction Not)
+lispToFunction _ _ (L.Symbol "and") = return $ lispToLogicFunction And
+lispToFunction _ _ (L.Symbol "or") = return $ lispToLogicFunction Or
+lispToFunction _ _ (L.Symbol "xor") = return $ lispToLogicFunction XOr
+lispToFunction _ _ (L.Symbol "=>") = return $ lispToLogicFunction Implies
+lispToFunction _ _ (L.Symbol "to_real")
+  = return $ ParsedFunction (const False) (\_ -> return $ AnyFunction ToReal)
+lispToFunction _ _ (L.Symbol "to_int")
+  = return$ ParsedFunction (const False) (\_ -> return $ AnyFunction ToInt)
+lispToFunction _ sort (L.Symbol "ite") = case sort of
+  Just (Sort tp)
+    -> return $ ParsedFunction (const False)
+       (\_ -> return $ AnyFunction (ITE tp))
+  Nothing -> return $ ParsedFunction (==1) $
+             \args -> case args of
+               [_,Just (Sort tp),_]
+                 -> return $ AnyFunction (ITE tp)
+               _ -> throwE $ "Invalid arguments to ite function."
+lispToFunction _ _ (L.Symbol "bvule") = return $ lispToBVCompFunction BVULE
+lispToFunction _ _ (L.Symbol "bvult") = return $ lispToBVCompFunction BVULT
+lispToFunction _ _ (L.Symbol "bvuge") = return $ lispToBVCompFunction BVUGE
+lispToFunction _ _ (L.Symbol "bvugt") = return $ lispToBVCompFunction BVUGT
+lispToFunction _ _ (L.Symbol "bvsle") = return $ lispToBVCompFunction BVSLE
+lispToFunction _ _ (L.Symbol "bvslt") = return $ lispToBVCompFunction BVSLT
+lispToFunction _ _ (L.Symbol "bvsge") = return $ lispToBVCompFunction BVSGE
+lispToFunction _ _ (L.Symbol "bvsgt") = return $ lispToBVCompFunction BVSGT
+lispToFunction _ sort (L.Symbol "bvadd") = lispToBVBinFunction sort BVAdd
+lispToFunction _ sort (L.Symbol "bvsub") = lispToBVBinFunction sort BVSub
+lispToFunction _ sort (L.Symbol "bvmul") = lispToBVBinFunction sort BVMul
+lispToFunction _ sort (L.Symbol "bvurem") = lispToBVBinFunction sort BVURem
+lispToFunction _ sort (L.Symbol "bvsrem") = lispToBVBinFunction sort BVSRem
+lispToFunction _ sort (L.Symbol "bvudiv") = lispToBVBinFunction sort BVUDiv
+lispToFunction _ sort (L.Symbol "bvsdiv") = lispToBVBinFunction sort BVSDiv
+lispToFunction _ sort (L.Symbol "bvshl") = lispToBVBinFunction sort BVSHL
+lispToFunction _ sort (L.Symbol "bvlshr") = lispToBVBinFunction sort BVLSHR
+lispToFunction _ sort (L.Symbol "bvashr") = lispToBVBinFunction sort BVASHR
+lispToFunction _ sort (L.Symbol "bvxor") = lispToBVBinFunction sort BVXor
+lispToFunction _ sort (L.Symbol "bvand") = lispToBVBinFunction sort BVAnd
+lispToFunction _ sort (L.Symbol "bvor") = lispToBVBinFunction sort BVOr
+lispToFunction _ sort (L.Symbol "bvnot") = lispToBVUnFunction sort BVNot
+lispToFunction _ sort (L.Symbol "bvneg") = lispToBVUnFunction sort BVNeg
+lispToFunction _ _ (L.Symbol "select")
+  = return $ ParsedFunction (==0)
+    (\args -> case args of
+       Just (Sort arr):_ -> case arr of
+         ArrayRepr idx el
+           -> return $ AnyFunction (Select idx el)
+         srt -> throwE $ "Invalid argument type to select function: "++show srt
+       _ -> throwE $ "Invalid arguments to select function.")
+lispToFunction _ sort (L.Symbol "store") = case sort of
+  Just (Sort srt) -> case srt of
+    ArrayRepr idx el
+      -> return (ParsedFunction (const False)
+                 (\_ -> return $ AnyFunction
+                        (Store idx el)))
+    srt' -> throwE $ "Invalid argument types to store function: "++show srt'
+  Nothing -> return $ ParsedFunction (==0)
+             (\args -> case args of
+                Just (Sort arr):_ -> case arr of
+                  ArrayRepr idx el
+                    -> return $ AnyFunction
+                       (Store idx el)
+                  srt -> throwE $ "Invalid first argument type to store function: "++show srt
+                _ -> throwE $ "Invalid arguments to store function.")
+lispToFunction r sort (L.List [L.Symbol "as",L.Symbol "const",sig]) = do
+  Sort rsig <- case sort of
+    Just srt -> return srt
+    Nothing -> lispToSort r sig
+  case rsig of
+    ArrayRepr idx el
+      -> return $ ParsedFunction (const False)
+         (\_ -> return $ AnyFunction (ConstArray idx el))
+    _ -> throwE $ "Invalid signature for (as const ...) function."
+lispToFunction _ sort (L.Symbol "concat")
+  = return $ ParsedFunction (const True)
+    (\args -> case args of
+       [Just (Sort tp1),Just (Sort tp2)]
+         -> case (tp1,tp2) of
+         (BitVecRepr sz1,BitVecRepr sz2)
+           -> return $ AnyFunction (Concat sz1 sz2)
+         _ -> throwE $ "Invalid argument types to concat function."
+       _ -> throwE $ "Wrong number of arguments to concat function.")
+lispToFunction _ sort (L.List [L.Symbol "_",L.Symbol "extract",L.Number (L.I end),L.Number (L.I start)])
+  = return $ ParsedFunction (==0)
+    (\args -> case args of
+       [Just (Sort srt)] -> case srt of
+         BitVecRepr size
+           | start <= end &&
+             end <= bwSize size
+             -> case TL.someNatVal start of
+               Just (TL.SomeNat start')
+                 -> case TL.someNatVal (end-start+1) of
+                      Just (TL.SomeNat len')
+                        -> return $ AnyFunction
+                            (Extract size (bw start')
+                              (bw len'))
+           | otherwise -> throwE $ "Invalid extract parameters."
+         srt -> throwE $ "Invalid type of extract argument: "++show srt
+       _ -> throwE $ "Wrong number of arguments to extract function.")
+lispToFunction _ sort (L.List [L.Symbol "_",L.Symbol "divisible",L.Number (L.I div)])
+  = return $ ParsedFunction (const False)
+    (\_ -> return $ AnyFunction (Divisible div))
+lispToFunction rf sort (L.List [sym,lispToList -> Just sig,tp]) = do
+  nsort <- lispToSort rf tp
+  fun <- lispToFunction rf (Just nsort) sym
+  rsig <- lispToSorts rf sig $
+          \sig' -> return $ runIdentity $ List.toList (\tp -> return $ Just (Sort tp)) sig'
+  return $ ParsedFunction (const False) (\_ -> getParsedFunction fun rsig)
+lispToFunction rf sort (L.Symbol name)
+  = parseFunction rf sort name
+    (p . Expr.Fun)
+    getCon
+    getTest
+    getField
+  where
+    p f = return $ ParsedFunction (const False) (const (return $ AnyFunction f))
+
+    getCon :: IsDatatype dt
+           => Datatype dt -> Constr dt csig
+           -> LispParse (ParsedFunction fun)
+    getCon (dt :: Datatype dt) con
+      = return $
+        ParsedFunction (case sort of
+                           Just _ -> const False
+                           Nothing -> \i -> List.indexDyn (fields con) i $
+                                            \f -> not $ Set.null $
+                                                  containedParameter
+                                                  (fieldType f) Set.empty)
+        (\argSorts -> case sort of
+            Just (Sort (DataRepr (dt'::Datatype dt') par)) -> case eqT :: Maybe (dt :~: dt') of
+              Nothing -> throwError "Type mismatch"
+              Just Refl -> return $ AnyFunction $ Expr.Constructor dt par con
+            Nothing -> case inferArgs argSorts (fields con) IMap.empty of
+              Nothing -> throwError "Cannot infer parameter type"
+              Just mp -> case fullArgs 0 (IMap.toList mp) (parameters dt) $
+                              \par -> AnyFunction $ Expr.Constructor
+                                      dt par con of
+                           Nothing -> throwError "Cannot infer parameter type"
+                           Just res -> return res)
+
+    getTest :: IsDatatype dt => Datatype dt -> Constr dt csig
+            -> LispParse (ParsedFunction fun)
+    getTest (dt :: Datatype dt) con
+      = return $
+        ParsedFunction (\i -> i==0 && (case parameters dt of
+                                         Zero -> False
+                                         _ -> True))
+        (\argSorts -> case parameters dt of
+            Zero -> return $ AnyFunction $ Expr.Test dt Nil con
+            _ -> case argSorts of
+              [Just (Sort (DataRepr (dt'::Datatype dt') par))] -> case eqT :: Maybe (dt :~: dt') of
+                Nothing -> throwError "Type mismatch"
+                Just Refl -> return $ AnyFunction $ Expr.Test dt par con)
+
+    getField :: IsDatatype dt => Datatype dt -> Field dt tp
+             -> LispParse (ParsedFunction fun)
+    getField (dt::Datatype dt) f
+      = return $
+        ParsedFunction (\i -> i==0 && (case parameters dt of
+                                         Zero -> False
+                                         _ -> True))
+        (\argSorts -> case parameters dt of
+            Zero -> return $ AnyFunction $ Expr.Field dt Nil f
+            _ -> case argSorts of
+              [Just (Sort (DataRepr (dt'::Datatype dt') par))] -> case eqT :: Maybe (dt :~: dt') of
+                Nothing -> throwError "Type mismatch"
+                Just Refl -> return $ AnyFunction $ Expr.Field dt par f
+              _ -> throwError "Cannot infer field type")
+                                       
+    inferArgs :: IsDatatype dt => [Maybe Sort] -> List (Field dt) tps -> IntMap Sort -> Maybe (IntMap Sort)
+    inferArgs [] Nil mp = Just mp
+    inferArgs (Nothing : args) (_ ::: fs) mp = inferArgs args fs mp
+    inferArgs (Just (Sort arg) : args) (f ::: fs) mp = do
+      mp1 <- typeInference arg (fieldType f)
+             (\p tp cmp -> let p' = fromInteger $ naturalToInteger p
+                           in case IMap.lookup p' cmp of
+                                Nothing -> Just $ IMap.insert p' (Sort tp) cmp
+                                Just (Sort tp') -> do
+                                  Refl <- geq tp tp'
+                                  return cmp) mp
+      inferArgs args fs mp1
+lispToFunction _ _ lsp = throwE $ "Unknown function: "++show lsp
+
+fullArgs :: Int -> [(Int,Sort)] -> Natural len -> (forall tps. (List.Length tps ~ len) => List Repr tps -> a) -> Maybe a
+fullArgs cpos [] Zero f = Just $ f Nil
+fullArgs cpos ((pos,Sort srt):srts) (Succ n) f
+  = if cpos==pos
+    then fullArgs (cpos+1) srts n $ \lst -> f (srt ::: lst)
+    else Nothing
+fullArgs _ _ _ _ = Nothing
+
+lispToOrdFunction :: OrdOp -> LispParse (ParsedFunction fun)
+lispToOrdFunction op
+  = return (ParsedFunction (==0)
+            (\argSrt -> case argSrt of
+               (Just (Sort srt)):_ -> case srt of
+                 IntRepr -> return $ AnyFunction (Ord NumInt op)
+                 RealRepr -> return $ AnyFunction (Ord NumReal op)
+                 srt' -> throwE $ "Invalid argument to "++show op++" function: "++show srt'
+               _ -> throwE $ "Wrong number of arguments to "++show op++" function."))
+
+lispToArithFunction :: Maybe Sort -> ArithOp -> LispParse (ParsedFunction fun)
+lispToArithFunction sort op = case sort of
+  Just (Sort tp) -> case tp of
+    IntRepr -> return (ParsedFunction (const False)
+                       (\args -> withEq IntRepr args $
+                                 \n _ -> return $ AnyFunction (Arith NumInt op n)))
+    RealRepr -> return (ParsedFunction (const False)
+                        (\args -> withEq RealRepr args $
+                                 \n _ -> return $ AnyFunction (Arith NumReal op n)))
+    srt -> throwE $ "Invalid type of "++show op++" function: "++show srt
+  Nothing -> return (ParsedFunction (==0)
+                     (\argSrt -> case argSrt of
+                        (Just (Sort srt)):_ -> case srt of
+                           IntRepr -> withEq IntRepr argSrt $
+                                      \n args
+                                      -> return $ AnyFunction (Arith NumInt op n)
+                           RealRepr -> withEq RealRepr argSrt $
+                                       \n args
+                                       -> return $ AnyFunction (Arith NumReal op n)
+                           srt' -> throwE $ "Wrong argument type to "++show op++" function: "++show srt'
+                        _ -> throwE $ "Wrong number of arguments to "++show op++" function."))
+
+lispToLogicFunction :: LogicOp -> ParsedFunction fun
+lispToLogicFunction op
+  = ParsedFunction (const False)
+    (\args -> withEq BoolRepr args $
+       \n args
+       -> return $ AnyFunction (Logic op n))
+
+lispToBVCompFunction :: BVCompOp -> ParsedFunction fun
+lispToBVCompFunction op
+  = ParsedFunction (==0)
+    (\args -> case args of
+       [Just (Sort srt),_] -> case srt of
+         BitVecRepr bw -> return $ AnyFunction (BVComp op bw)
+         srt -> throwE $ "Invalid argument type to "++show op++" function: "++show srt
+       _ -> throwE $ "Wrong number of arguments to "++show op++" function.")
+
+lispToBVBinFunction :: Maybe Sort -> BVBinOp -> LispParse (ParsedFunction fun)
+lispToBVBinFunction (Just (Sort srt)) op = case srt of
+  BitVecRepr bw -> return $ ParsedFunction (const False) $
+                   \_ -> return $ AnyFunction (BVBin op bw)
+  srt' -> throwE $ "Invalid argument type to "++show op++" function: "++show srt'
+lispToBVBinFunction Nothing op
+  = return $ ParsedFunction (==0) $
+    \args -> case args of
+      [Just (Sort srt),_] -> case srt of
+        BitVecRepr bw -> return $ AnyFunction (BVBin op bw)
+        srt' -> throwE $ "Invalid argument type to "++show op++" function: "++show srt'
+      _ -> throwE $ "Wrong number of arguments to "++show op++" function."
+
+lispToBVUnFunction :: Maybe Sort -> BVUnOp -> LispParse (ParsedFunction fun)
+lispToBVUnFunction (Just (Sort srt)) op = case srt of
+  BitVecRepr bw -> return $ ParsedFunction (const False) $
+                   \_ -> return $ AnyFunction (BVUn op bw)
+  srt' -> throwE $ "Invalid argument type to "++show op++" function: "++show srt'
+lispToBVUnFunction Nothing op
+  = return $ ParsedFunction (==0) $
+    \args -> case args of
+      [Just (Sort srt)] -> case srt of
+        BitVecRepr bw -> return $ AnyFunction (BVUn op bw)
+        srt' -> throwE $ "Invalid argument type to "++show op++" function: "++show srt'
+      _ -> throwE $ "Wrong number of arguments to "++show op++" function."
+
+mkMap :: List Repr idx -> AnyFunction fun -> AnyFunction fun
+mkMap idx (AnyFunction f) = AnyFunction (Map idx f)
+
+asArraySort :: Sort -> Maybe (Sorts,Sort)
+asArraySort (Sort tp) = case tp of
+  ArrayRepr idx el
+    -> return (Sorts idx,Sort el)
+  _ -> Nothing
+
+lispToList :: L.Lisp -> Maybe [L.Lisp]
+lispToList (L.Symbol "()") = Just []
+lispToList (L.List lst) = Just lst
+lispToList _ = Nothing
+
+lispToSort :: LispParser v qv fun fv lv e -> L.Lisp -> LispParse Sort
+lispToSort _ (L.Symbol "Bool") = return (Sort BoolRepr)
+lispToSort _ (L.Symbol "Int") = return (Sort IntRepr)
+lispToSort _ (L.Symbol "Real") = return (Sort RealRepr)
+lispToSort r (L.List ((L.Symbol "Array"):tps)) = do
+  Sort rtp' <- lispToSort r rtp
+  lispToSorts r idx (\idx' -> return $ Sort (ArrayRepr idx' rtp'))
+  where
+    (idx,rtp) = splitLast tps
+    splitLast [x] = ([],x)
+    splitLast (x:xs) = let (xs',y') = splitLast xs
+                       in (x:xs',y')
+lispToSort _ (L.List [L.Symbol "_",L.Symbol "BitVec",L.Number (L.I n)])
+  = case TL.someNatVal n of
+      Just (TL.SomeNat w) -> return (Sort (BitVecRepr (bw w)))
+lispToSort r (L.Symbol name)
+  = parseDatatype r name $ \dt -> case geq (parameters dt) Zero of
+  Just Refl -> return $ Sort (DataRepr dt Nil)
+  Nothing -> throwE $ "Wrong sort for type "++show name
+lispToSort r (L.List (L.Symbol name:args))
+  = parseDatatype r name $
+    \dt -> lispToSorts r args $
+           \args' -> case geq (List.length args') (parameters dt) of
+             Just Refl -> return $ Sort (DataRepr dt args')
+             Nothing -> throwE $ "Wrong number of arguments for type "++show name
+lispToSort _ lsp = throwE $ "Invalid SMT type: "++show lsp
+
+lispToSorts :: LispParser v qv fun fv lv e -> [L.Lisp]
+            -> (forall (arg :: [Type]). List Repr arg -> LispParse a)
+            -> LispParse a
+lispToSorts _ [] f = f Nil
+lispToSorts r (x:xs) f = do
+  Sort tp <- lispToSort r x
+  lispToSorts r xs $
+    \tps -> f (tp ::: tps)
+
+lispToValue :: SMTPipe -> Maybe Sort -> L.Lisp -> LispParse AnyValue
+lispToValue b hint l = case runExcept $ lispToConstant l of
+  Right r -> return r
+  Left e -> lispToConstrConstant b hint l
+
+lispToConstant :: L.Lisp -> LispParse AnyValue
+lispToConstant (L.Symbol "true") = return (AnyValue (BoolValue True))
+lispToConstant (L.Symbol "false") = return (AnyValue (BoolValue False))
+lispToConstant (lispToNumber -> Just n) = return (AnyValue (IntValue n))
+lispToConstant (lispToReal -> Just n) = return (AnyValue (RealValue n))
+lispToConstant (lispToBitVec -> Just (val,sz))
+  = case TL.someNatVal sz of
+  Just (TL.SomeNat w) -> return (AnyValue (BitVecValue val (bw w)))
+lispToConstant l = throwE $ "Invalid constant "++show l
+
+lispToConstrConstant :: SMTPipe -> Maybe Sort -> L.Lisp
+                     -> LispParse AnyValue
+lispToConstrConstant b hint sym = do
+  (constr,args) <- case sym of
+    L.Symbol s -> return (s,[])
+    L.List ((L.Symbol s):args) -> return (s,args)
+    _ -> throwE $ "Invalid constant: "++show sym
+  case Map.lookup constr (allConstructors $ datatypes b) of
+    Just (AnyConstr (dt::Datatype dt) con)
+      -> makeList (case hint of
+                     Just (Sort (DataRepr dt' par))
+                       -> IMap.fromList $ runIdentity $ List.toListIndex
+                          (\i srt -> return (fromInteger $ naturalToInteger i,
+                                             Sort srt))
+                          par
+                     Nothing -> IMap.empty) (fields con) args $
+         \par rargs -> case fullArgs 0 (IMap.toList par) (parameters dt) $
+                            \rpar -> case instantiate
+                                          (runIdentity $ List.mapM
+                                           (return.fieldType) (fields con))
+                                          rpar of
+                              (tsig,Refl) -> do
+                                Refl <- geq tsig
+                                        (runIdentity $ List.mapM
+                                         (return.getType) rargs)
+                                return $ AnyValue $ DataValue $
+                                  construct rpar con rargs of
+           Just (Just res) -> return res
+           _ -> throwE "Type error in constructor"
+    Nothing -> throwE $ "Invalid constructor "++show constr
+  where
+    makeList :: IsDatatype dt
+             => IntMap Sort
+             -> List (Type.Field dt) arg
+             -> [L.Lisp]
+             -> (forall narg. List.Length arg ~ List.Length narg
+                 => IntMap Sort -> List Value narg -> LispParse a)
+             -> LispParse a
+    makeList par Nil [] res = res par Nil
+    makeList _ Nil _ _ = throwE $ "Too many arguments to constructor."
+    makeList par (f ::: fs) (l:ls) res
+      = partialInstantiation (fieldType f)
+        (\n g -> do
+            Sort parTp <- IMap.lookup (fromInteger $ naturalToInteger n) par
+            return $ g parTp) $
+        \ftp -> do
+          AnyValue v <- lispToValue b (Just $ Sort ftp) l
+          case typeInference ftp (valueType v)
+               (\pos ptp cpar -> let pos' = fromInteger $ naturalToInteger pos
+                                 in case IMap.lookup pos' cpar of
+                   Just (Sort ptp') -> case geq ptp ptp' of
+                     Just Refl -> return cpar
+                     Nothing -> Nothing
+                   Nothing -> return $ IMap.insert pos' (Sort ptp) cpar) par of
+            Nothing -> throwE "Type error in constructor arguments."
+            Just npar -> makeList npar fs ls $
+                         \rpar rest -> res rpar (v ::: rest)
+    makeList _ (_ ::: _) [] _ = throwE $ "Not enough arguments to constructor."
+
+lispToNumber :: L.Lisp -> Maybe Integer
+lispToNumber (L.Number (L.I n)) = Just n
+lispToNumber (L.List [L.Symbol "-",n]) = do
+  n' <- lispToNumber n
+  return (negate n')
+lispToNumber _ = Nothing
+
+lispToReal :: L.Lisp -> Maybe Rational
+lispToReal (L.Number (L.D n)) = Just $ toRational n
+lispToReal (L.Number (L.I n)) = Just $ fromInteger n
+lispToReal (L.List [L.Symbol "/",v1,v2]) = do
+  r1 <- lispToReal v1
+  r2 <- lispToReal v2
+  return $ r1 / r2
+lispToReal (L.List [L.Symbol "-",v]) = do
+  r <- lispToReal v
+  return $ -r
+lispToReal _ = Nothing
+
+lispToBitVec :: L.Lisp -> Maybe (Integer,Integer)
+lispToBitVec (L.List [L.Symbol "_",L.Symbol (T.stripPrefix "bv" -> Just val),L.Number (L.I sz)])
+  = case T.decimal val of
+  Right (rval,"") -> Just (rval,sz)
+  _ -> Nothing
+lispToBitVec (L.Symbol (T.stripPrefix "#x" -> Just bv)) = case T.hexadecimal bv of
+  Right (rbv,"") -> Just (rbv,(fromIntegral $ T.length bv)*4)
+  _ -> Nothing
+lispToBitVec (L.Symbol (T.stripPrefix "#b" -> Just bv))
+  | T.all (\c -> c=='0' || c=='1') bv = Just (T.foldl (\v c -> case c of
+                                                         '0' -> v*2
+                                                         '1' -> v*2+1) 0 bv,
+                                              fromIntegral $ T.length bv)
+  | otherwise = Nothing
+lispToBitVec _ = Nothing
+
+exprToLisp :: TypeRegistry T.Text T.Text T.Text
+           -> Expression PipeVar PipeVar PipeFun PipeVar PipeVar (Expr SMTPipe) t
+           -> L.Lisp
+exprToLisp reg
+  = runIdentity . exprToLispWith
+    (\(UntypedVar v _) -> return $ L.Symbol v)
+    (\(UntypedVar v _) -> return $ L.Symbol v)
+    (\(UntypedFun v _ _) -> return $ L.Symbol v)
+    (\dt con -> case Map.lookup (AnyConstr dt con) (revConstructors reg) of
+        Just sym -> return $ L.Symbol sym)
+    (\dt con -> case Map.lookup (AnyConstr dt con) (revConstructors reg) of
+        Just sym -> return $ L.Symbol $ T.append "is-" sym)
+    (\dt field -> case Map.lookup (AnyField dt field) (revFields reg) of
+        Just sym -> return $ L.Symbol sym)
+    (\(UntypedVar v _) -> return $ L.Symbol v)
+    (\(UntypedVar v _) -> return $ L.Symbol v)
+    (\(PipeExpr v) -> return $ exprToLisp reg v)
+
+exprToLispWith :: (Monad m,GetType v,GetType qv,GetType fv,GetType lv,GetFunType fun,GetType e)
+               => (forall (t' :: Type).
+                   v t' -> m L.Lisp)                         -- ^ variables
+               -> (forall (t' :: Type).
+                   qv t' -> m L.Lisp)                        -- ^ quantified variables
+               -> (forall (arg :: [Type]) (res :: Type).
+                   fun '(arg,res) -> m L.Lisp) -- ^ functions
+               -> (forall (arg :: [Type]) (dt :: [Type] -> (Type -> *) -> *).
+                   IsDatatype dt =>
+                   Datatype dt -> Type.Constr dt arg -> m L.Lisp)     -- ^ constructor
+               -> (forall (arg :: [Type]) (dt :: [Type] -> (Type -> *) -> *).
+                   IsDatatype dt =>
+                   Datatype dt -> Type.Constr dt arg -> m L.Lisp)     -- ^ constructor tests
+               -> (forall (dt :: [Type] -> (Type -> *) -> *) (res :: Type).
+                   IsDatatype dt =>
+                   Datatype dt -> Type.Field dt res -> m L.Lisp) -- ^ field accesses
+               -> (forall t.
+                   fv t -> m L.Lisp)                                              -- ^ function variables
+               -> (forall t.
+                   lv t -> m L.Lisp)                                              -- ^ let variables
+               -> (forall (t' :: Type).
+                   e t' -> m L.Lisp)                         -- ^ sub expressions
+               -> Expression v qv fun fv lv e t
+               -> m L.Lisp
+exprToLispWith f _ _ _ _ _ _ _ _ (Expr.Var v) = f v
+exprToLispWith _ f _ _ _ _ _ _ _ (Expr.QVar v) = f v
+exprToLispWith _ _ _ _ _ _ f _ _ (Expr.FVar v) = f v
+exprToLispWith _ _ _ _ _ _ _ f _ (Expr.LVar v) = f v
+-- This is a special case because the argument order is different
+exprToLispWith _ _ f g h i _ _ j (Expr.App (Store _ _) (arr ::: val ::: idx)) = do
+  arr' <- j arr
+  idx' <- List.toList j idx
+  val' <- j val
+  return $ L.List ((L.Symbol "store"):arr':idx'++[val'])
+exprToLispWith _ _ f g h i _ _ j e@(Expr.App fun args) = do
+  let needAs = case fun of
+        Constructor dt par con -> not $ determines dt con
+        _ -> False
+  args' <- List.toList j args
+  sym <- functionSymbol f g h i fun
+  let c = case args' of
+            [] -> sym
+            _ -> L.List $ sym:args'
+      rc = if needAs
+           then L.List [L.Symbol "as",c,typeSymbol Set.empty (getType e)]
+           else c
+  return rc
+
+exprToLispWith _ _ _ f _ _ _ _ _ (Expr.Const val) = valueToLisp f val
+exprToLispWith _ _ f g h i _ _ _ (Expr.AsArray fun) = do
+  sym <- functionSymbolWithSig f g h i fun
+  return $  L.List [L.Symbol "_"
+                   ,L.Symbol "as-array"
+                   ,sym]
+exprToLispWith _ f _ _ _ _ _ _ g (Expr.Quantification q args body) = do
+  bind <- List.toList (\arg -> do
+                          sym <- f arg
+                          return $ L.List [sym,typeSymbol Set.empty $ getType arg]
+                      ) args
+  body' <- g body
+  return $ L.List [L.Symbol (case q of
+                               Expr.Forall -> "forall"
+                               Expr.Exists -> "exists")
+                  ,L.List bind
+                  ,body']
+exprToLispWith _ _ _ _ _ _ _ f g (Expr.Let args body) = do
+  binds <- List.toList (\bind -> do
+                          sym <- f (letVar bind)
+                          expr <- g (letExpr bind)
+                          return $ L.List [sym,expr]
+                       ) args
+  body' <- g body
+  return $ L.List [L.Symbol "let"
+                  ,L.List binds
+                  ,body']
+
+valueToLisp :: Monad m
+            => (forall arg tp. (IsDatatype tp)
+                => Datatype tp -> Type.Constr tp arg -> m L.Lisp)
+            -> Value t -> m L.Lisp
+valueToLisp _ (BoolValue True) = return $ L.Symbol "true"
+valueToLisp _ (BoolValue False) = return $ L.Symbol "false"
+valueToLisp _ (IntValue n) = return $ numToLisp n
+valueToLisp _ (RealValue n)
+  = return $ L.List [L.Symbol "/"
+                    ,numToLisp $ numerator n
+                    ,numToLisp $ denominator n]
+valueToLisp _ (BitVecValue n bw)
+  = return $ L.List [L.Symbol "_"
+                    ,L.Symbol (T.pack $ "bv"++show rn)
+                    ,L.Number $ L.I bw']
+  where
+    bw' = bwSize bw
+    rn = n `mod` 2^bw'
+valueToLisp f v@(DataValue val) = do
+  let (dt,par) = datatypeGet val
+  case deconstruct val of
+    ConApp { constructor = con
+           , arguments = args } -> do
+      let needAs = not $ determines dt con
+      con' <- f dt con
+      args' <- List.toList (valueToLisp f) args
+      let c = case args' of
+                [] -> con'
+                xs -> L.List (con' : xs)
+          rc = if needAs
+               then L.List [L.Symbol "as",c,typeSymbol Set.empty
+                                            (getType v)]
+               else c
+      return rc
+
+isOverloaded :: Function fun sig -> Bool
+isOverloaded (Expr.Eq _ _) = True
+isOverloaded (Expr.Distinct _ _) = True
+isOverloaded (Expr.Map _ _) = True
+isOverloaded (Expr.Ord _ _) = True
+isOverloaded (Expr.Arith _ _ _) = True
+isOverloaded (Expr.Abs _) = True
+isOverloaded (Expr.ITE _) = True
+isOverloaded (Expr.BVComp _ _) = True
+isOverloaded (Expr.BVBin _ _) = True
+isOverloaded (Expr.BVUn _ _) = True
+isOverloaded (Expr.Select _ _) = True
+isOverloaded (Expr.Store _ _) = True
+isOverloaded (Expr.ConstArray _ _) = True
+isOverloaded (Expr.Concat _ _) = True
+isOverloaded (Expr.Extract _ _ _) = True
+isOverloaded _ = False
+
+functionSymbol :: (Monad m,GetFunType fun)
+               => (forall (arg' :: [Type]) (res' :: Type).
+                   fun '(arg',res') -> m L.Lisp) -- ^ How to render user functions
+               -> (forall (arg' :: [Type]) (dt :: [Type] -> (Type -> *) -> *).
+                   IsDatatype dt =>
+                   Datatype dt -> Type.Constr dt arg' -> m L.Lisp)    -- ^ How to render constructor applications
+               -> (forall (arg' :: [Type]) (dt :: [Type] -> (Type -> *) -> *).
+                   IsDatatype dt =>
+                   Datatype dt -> Type.Constr dt arg' -> m L.Lisp)    -- ^ How to render constructor tests
+               -> (forall (dt :: [Type] -> (Type -> *) -> *) (res' :: Type).
+                   IsDatatype dt =>
+                   Datatype dt -> Type.Field dt res' -> m L.Lisp)          -- ^ How to render field acceses
+               -> Function fun '(arg,res) -> m L.Lisp
+functionSymbol f _ _ _ (Expr.Fun g) = f g
+functionSymbol _ _ _ _ (Expr.Eq _ _) = return $ L.Symbol "="
+functionSymbol _ _ _ _ (Expr.Distinct _ _) = return $ L.Symbol "distinct"
+functionSymbol f g h i (Expr.Map _ j) = do
+  sym <- functionSymbolWithSig f g h i j
+  return $  L.List [L.Symbol "_"
+                   ,L.Symbol "map"
+                   ,sym]
+functionSymbol _ _ _ _ (Ord _ op) = return $ ordSymbol op
+functionSymbol _ _ _ _ (Arith _ op _) = return $ arithSymbol op
+functionSymbol _ _ _ _ (ArithIntBin Div) = return $ L.Symbol "div"
+functionSymbol _ _ _ _ (ArithIntBin Mod) = return $ L.Symbol "mod"
+functionSymbol _ _ _ _ (ArithIntBin Rem) = return $ L.Symbol "rem"
+functionSymbol _ _ _ _ Divide = return $ L.Symbol "/"
+functionSymbol _ _ _ _ (Abs _) = return $ L.Symbol "abs"
+functionSymbol _ _ _ _ Not = return $ L.Symbol "not"
+functionSymbol _ _ _ _ (Logic And _) = return $ L.Symbol "and"
+functionSymbol _ _ _ _ (Logic Or _) = return $ L.Symbol "or"
+functionSymbol _ _ _ _ (Logic XOr _) = return $ L.Symbol "xor"
+functionSymbol _ _ _ _ (Logic Implies _) = return $ L.Symbol "=>"
+functionSymbol _ _ _ _ ToReal = return $ L.Symbol "to_real"
+functionSymbol _ _ _ _ ToInt = return $ L.Symbol "to_int"
+functionSymbol _ _ _ _ (ITE _) = return $ L.Symbol "ite"
+functionSymbol _ _ _ _ (BVComp op _) = return $ L.Symbol $ case op of
+  BVULE -> "bvule"
+  BVULT -> "bvult"
+  BVUGE -> "bvuge"
+  BVUGT -> "bvugt"
+  BVSLE -> "bvsle"
+  BVSLT -> "bvslt"
+  BVSGE -> "bvsge"
+  BVSGT -> "bvsgt"
+functionSymbol _ _ _ _ (BVBin op _) = return $ L.Symbol $ case op of
+  BVAdd -> "bvadd"
+  BVSub -> "bvsub"
+  BVMul -> "bvmul"
+  BVURem -> "bvurem"
+  BVSRem -> "bvsrem"
+  BVUDiv -> "bvudiv"
+  BVSDiv -> "bvsdiv"
+  BVSHL -> "bvshl"
+  BVLSHR -> "bvlshr"
+  BVASHR -> "bvashr"
+  BVXor -> "bvxor"
+  BVAnd -> "bvand"
+  BVOr -> "bvor"
+functionSymbol _ _ _ _ (BVUn op _) = return $ L.Symbol $ case op of
+  BVNot -> "bvnot"
+  BVNeg -> "bvneg"
+functionSymbol _ _ _ _ (Select _ _) = return $ L.Symbol "select"
+functionSymbol _ _ _ _ (Store _ _) = return $ L.Symbol "store"
+functionSymbol _ _ _ _ (ConstArray idx el)
+  = return $ L.List [L.Symbol "as"
+                    ,L.Symbol "const"
+                    ,typeSymbol Set.empty (ArrayRepr idx el)]
+functionSymbol _ _ _ _ (Concat _ _) = return $ L.Symbol "concat"
+functionSymbol _ _ _ _ (Extract bw start len)
+  = return $ L.List [L.Symbol "_"
+                    ,L.Symbol "extract"
+                    ,L.Number $ L.I $ start'+len'-1
+                    ,L.Number $ L.I start']
+  where
+    start' = bwSize start
+    len' = bwSize len
+functionSymbol _ g _ _ (Constructor dt par con) = g dt con
+functionSymbol _ _ h _ (Test dt par con) = h dt con
+functionSymbol _ _ _ i (Expr.Field dt par f) = i dt f
+functionSymbol _ _ _ _ (Divisible n) = return $ L.List [L.Symbol "_"
+                                                       ,L.Symbol "divisible"
+                                                       ,L.Number $ L.I n]
+
+functionSymbolWithSig :: (Monad m,GetFunType fun)
+                      => (forall (arg' :: [Type]) (res' :: Type).
+                          fun '(arg',res') -> m L.Lisp) -- ^ How to render user functions
+                      -> (forall (arg' :: [Type])
+                          (dt :: [Type] -> (Type -> *) -> *).
+                          IsDatatype dt =>
+                          Datatype dt -> Type.Constr dt arg' -> m L.Lisp)    -- ^ How to render constructor applications
+                      -> (forall (arg' :: [Type])
+                          (dt :: [Type] -> (Type -> *) -> *).
+                          IsDatatype dt =>
+                          Datatype dt -> Type.Constr dt arg' -> m L.Lisp)    -- ^ How to render constructor tests
+                      -> (forall (dt :: [Type] -> (Type -> *) -> *)
+                          (res' :: Type).
+                          IsDatatype dt =>
+                          Datatype dt -> Type.Field dt res' -> m L.Lisp)          -- ^ How to render field acceses
+                      -> Function fun '(arg,res) -> m L.Lisp
+functionSymbolWithSig f g h i j = do
+  sym <- functionSymbol f g h i j
+  if isOverloaded j
+    then return $ L.List [sym
+                         ,typeList arg
+                         ,typeSymbol Set.empty res]
+    else return sym
+  where
+    (arg,res) = getFunType j
+
+typeSymbol :: Set String -> Repr t -> L.Lisp
+typeSymbol _ BoolRepr = L.Symbol "Bool"
+typeSymbol _ IntRepr = L.Symbol "Int"
+typeSymbol _ RealRepr = L.Symbol "Real"
+typeSymbol _ (BitVecRepr n) = L.List [L.Symbol "_"
+                                     ,L.Symbol "BitVec"
+                                     ,L.Number (L.I $ bwSize n)]
+typeSymbol recDt (ArrayRepr idx el)
+  = L.List ((L.Symbol "Array"):
+            runIdentity (List.toList (return.typeSymbol recDt) idx) ++
+            [typeSymbol recDt el])
+typeSymbol recDt (DataRepr dt par)
+  | Set.member (datatypeName dt) recDt
+    = L.Symbol (T.pack $ datatypeName dt)
+  | otherwise = L.List $ [L.Symbol (T.pack $ datatypeName dt)]++
+                (runIdentity $ List.toList (return.typeSymbol recDt) par)
+typeSymbol _ (ParameterRepr n)
+  = L.Symbol (T.pack $ "a"++show (naturalToInteger n))
+                       
+
+typeList :: List Repr t -> L.Lisp
+typeList Nil = L.Symbol "()"
+typeList args = L.List (runIdentity $ List.toList
+                        (return.typeSymbol Set.empty) args)
+
+ordSymbol :: OrdOp -> L.Lisp
+ordSymbol Ge = L.Symbol ">="
+ordSymbol Gt = L.Symbol ">"
+ordSymbol Le = L.Symbol "<="
+ordSymbol Lt = L.Symbol "<"
+
+arithSymbol :: ArithOp -> L.Lisp
+arithSymbol Plus = L.Symbol "+"
+arithSymbol Mult = L.Symbol "*"
+arithSymbol Minus = L.Symbol "-"
+
+numToLisp :: Integer -> L.Lisp
+numToLisp n = if n>=0
+              then L.Number $ L.I n
+              else L.List [L.Symbol "-"
+                          ,L.Number $ L.I $ abs n]
+
+clearInput :: SMTPipe -> IO ()
+clearInput pipe = do
+  r <- hReady (channelOut pipe)
+  if r
+    then (do
+             _ <- BS.hGetSome (channelOut pipe) 1024
+             clearInput pipe)
+    else return ()
+
+putRequest :: SMTPipe -> L.Lisp -> IO ()
+putRequest pipe expr = do
+  clearInput pipe
+  toByteStringIO (BS.hPutStr $ channelIn pipe) (mappend (L.fromLispExpr expr) flush)
+  BS8.hPutStrLn (channelIn pipe) ""
+  hFlush (channelIn pipe)
+
+parseResponse :: SMTPipe -> IO L.Lisp
+parseResponse pipe = do
+  str <- BS.hGetLine (channelOut pipe)
+  let continue (Done _ r) = return r
+      continue res@(Partial _) = do
+        line <- BS.hGetLine (channelOut pipe)
+        continue (feed (feed res line) (BS8.singleton '\n'))
+      continue (Fail str' ctx msg) = error $ "Error parsing "++show str'++" response in "++show ctx++": "++msg
+  continue $ parse L.lisp (BS8.snoc str '\n')
+
+genName :: SMTPipe -> String -> (T.Text,SMTPipe)
+genName pipe name = (sym,pipe { names = nnames })
+  where
+    (sym,nnames) = genName' (names pipe) name
+
+genName' :: Map String Int -> String -> (T.Text,Map String Int)
+genName' names name = case Map.lookup name names of
+  Nothing -> (T.pack name',Map.insert name 0 names)
+  Just n -> (T.pack $ name' ++ "_" ++ show (n+1),
+             Map.insert name (n+1) names)
+  where
+    name' = escapeName name
+    escapeName :: String -> String
+    escapeName [] = []
+    escapeName ('_':xs) = '_':'_':escapeName xs
+    escapeName (x:xs) = x:escapeName xs
+
+tacticToLisp :: Tactic -> L.Lisp
+tacticToLisp Skip = L.Symbol "skip"
+tacticToLisp (AndThen ts) = L.List ((L.Symbol "and-then"):fmap tacticToLisp ts)
+tacticToLisp (OrElse ts) = L.List ((L.Symbol "or-else"):fmap tacticToLisp ts)
+tacticToLisp (ParOr ts) = L.List ((L.Symbol "par-or"):fmap tacticToLisp ts)
+tacticToLisp (ParThen t1 t2) = L.List [L.Symbol "par-then"
+                                      ,tacticToLisp t1
+                                      ,tacticToLisp t2]
+tacticToLisp (TryFor t n) = L.List [L.Symbol "try-for"
+                                   ,tacticToLisp t
+                                   ,L.Number $ L.I n]
+tacticToLisp (If c t1 t2) = L.List [L.Symbol "if"
+                                   ,probeToLisp c
+                                   ,tacticToLisp t1
+                                   ,tacticToLisp t2]
+tacticToLisp (FailIf c) = L.List [L.Symbol "fail-if"
+                                 ,probeToLisp c]
+tacticToLisp (UsingParams (CustomTactic name) []) = L.Symbol (T.pack name)
+tacticToLisp (UsingParams (CustomTactic name) pars)
+  = L.List ([L.Symbol "using-params"
+            ,L.Symbol $ T.pack name]++
+            concat [ [L.Symbol (T.pack $ ':':pname)
+                     ,case par of
+                         ParBool True -> L.Symbol "true"
+                         ParBool False -> L.Symbol "false"
+                         ParInt i -> L.Number $ L.I i
+                         ParDouble i -> L.Number $ L.D i]
+                     | (pname,par) <- pars ])
+
+probeToLisp :: Probe a -> L.Lisp
+probeToLisp (ProbeBoolConst b)
+  = L.Symbol $ if b then "true" else "false"
+probeToLisp (ProbeIntConst i)
+  = L.Number $ L.I i
+probeToLisp (ProbeAnd ps)
+  = L.List ((L.Symbol "and"):
+            fmap probeToLisp ps)
+probeToLisp (ProbeOr ps)
+  = L.List ((L.Symbol "or"):
+            fmap probeToLisp ps)
+probeToLisp (ProbeNot p)
+  = L.List [L.Symbol "not"
+           ,probeToLisp p]
+probeToLisp (ProbeEq p1 p2)
+  = L.List [L.Symbol "="
+           ,probeToLisp p1
+           ,probeToLisp p2]
+probeToLisp (ProbeGt p1 p2)
+  = L.List [L.Symbol ">"
+           ,probeToLisp p1
+           ,probeToLisp p2]
+probeToLisp (ProbeGe p1 p2)
+  = L.List [L.Symbol ">="
+           ,probeToLisp p1
+           ,probeToLisp p2]
+probeToLisp (ProbeLt p1 p2)
+  = L.List [L.Symbol "<"
+           ,probeToLisp p1
+           ,probeToLisp p2]
+probeToLisp (ProbeGe p1 p2)
+  = L.List [L.Symbol "<="
+           ,probeToLisp p1
+           ,probeToLisp p2]
+probeToLisp IsPB = L.Symbol "is-pb"
+probeToLisp ArithMaxDeg = L.Symbol "arith-max-deg"
+probeToLisp ArithAvgDeg = L.Symbol "arith-avg-deg"
+probeToLisp ArithMaxBW = L.Symbol "arith-max-bw"
+probeToLisp ArithAvgBW = L.Symbol "arith-avg-bw"
+probeToLisp IsQFLIA = L.Symbol "is-qflia"
+probeToLisp IsQFLRA = L.Symbol "is-qflra"
+probeToLisp IsQFLIRA = L.Symbol "is-qflira"
+probeToLisp IsILP = L.Symbol "is-ilp"
+probeToLisp IsQFNIA = L.Symbol "is-qfnia"
+probeToLisp IsQFNRA = L.Symbol "is-qfnra"
+probeToLisp IsNIA = L.Symbol "is-nia"
+probeToLisp IsNRA = L.Symbol "is-nra"
+probeToLisp IsUnbounded = L.Symbol "is-unbounded"
+probeToLisp Memory = L.Symbol "memory"
+probeToLisp Depth = L.Symbol "depth"
+probeToLisp Size = L.Symbol "size"
+probeToLisp NumExprs = L.Symbol "num-exprs"
+probeToLisp NumConsts = L.Symbol "num-consts"
+probeToLisp NumBoolConsts = L.Symbol "num-bool-consts"
+probeToLisp NumArithConsts = L.Symbol "num-arith-consts"
+probeToLisp NumBVConsts = L.Symbol "num-bv-consts"
+probeToLisp Strat.ProduceProofs = L.Symbol "produce-proofs"
+probeToLisp ProduceModel = L.Symbol "produce-model"
+probeToLisp Strat.ProduceUnsatCores = L.Symbol "produce-unsat-cores"
+probeToLisp HasPatterns = L.Symbol "has-patterns"
+probeToLisp IsPropositional = L.Symbol "is-propositional"
+probeToLisp IsQFBV = L.Symbol "is-qfbv"
+probeToLisp IsQFBVEQ = L.Symbol "is-qfbv-eq"
diff --git a/Setup.hs b/Setup.hs
new file mode 100644
--- /dev/null
+++ b/Setup.hs
@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain
diff --git a/smtlib2-pipe.cabal b/smtlib2-pipe.cabal
new file mode 100644
--- /dev/null
+++ b/smtlib2-pipe.cabal
@@ -0,0 +1,29 @@
+Name:           smtlib2-pipe
+Version:        1.0
+Author:         Henning Günther <guenther@forsyte.at>
+Maintainer:     guenther@forsyte.at
+Synopsis:       A type-safe interface to communicate with an SMT solver.
+Stability:      provisional
+Category:       SMT, Formal Methods, Theorem Provers, Symbolic Computation
+License:        GPL-3
+License-File:   LICENSE
+Build-Type:     Simple
+Cabal-Version:  >=1.8
+
+Source-Repository head
+  Type:         git
+  Location:     https://github.com/hguenther/smtlib2.git
+
+Library
+  Build-Depends: smtlib2 >= 1.0 && < 1.1, base >=4 && <5, text, containers, process, atto-lisp >=0.2, attoparsec, mtl, bytestring, blaze-builder, dependent-sum, transformers
+  Extensions: GADTs,FlexibleContexts,FlexibleInstances,ExistentialQuantification,KindSignatures,DataKinds,TypeFamilies,AllowAmbiguousTypes,TypeOperators,MultiParamTypeClasses,OverloadedStrings,ScopedTypeVariables,RankNTypes,GeneralizedNewtypeDeriving,ViewPatterns,CPP,StandaloneDeriving,DeriveDataTypeable
+  GHC-Options: -fwarn-unused-imports
+  Exposed-Modules:
+    Language.SMTLib2.Pipe
+    Language.SMTLib2.Pipe.Internals
+
+Test-Suite test-smtlib2-pipe
+  Type: detailed-0.9
+  Test-Module: PipeTest
+  Hs-Source-Dirs: test
+  Build-Depends: base >=4 && <5, smtlib2, smtlib2-pipe==1.0, smtlib2-quickcheck >= 1.0 && < 1.1, Cabal, cabal-test-quickcheck
diff --git a/test/PipeTest.hs b/test/PipeTest.hs
new file mode 100644
--- /dev/null
+++ b/test/PipeTest.hs
@@ -0,0 +1,12 @@
+module PipeTest where
+
+import Language.SMTLib2.Pipe
+import Language.SMTLib2.QuickCheck
+
+import Distribution.TestSuite
+import Distribution.TestSuite.QuickCheck
+import Data.Either
+
+tests :: IO [Test]
+tests = return [testProperty "round-trip"
+                (roundTripTest emptyContext (createPipe "z3" ["-smt2","-in"]))]
