README.html

<h1>Extensible Haskell front-end for the Programatica project</h1>

<h2>What is in this directory (base/AST)</h2>

This directory defines datatypes and associated functions for the
nonrecursive part of the structure of the base abstract syntax. These types
and functions should be reusable in extended versions of the language.

<p>
The modules are factorized according to syntactic category and functionality.
This is illustrated in the following table:

<p>
<table border=1>
<caption>For every x, there is a module called
<code>Hs</code>&lt;<var>category</var>&gt;&lt<var>functionality</var>&gt;
</caption>
<tr><th><th>Decl<th>Exp<th>Fields<th>Guards<th>Kind<th>Pat<th>Type<th>collected
<tr><th>Struct<td>x<td>x<td>x<td>x<td>x<td>x<td>x<td>BaseSyntaxStruct
<tr><th>Maps<td>x<td>x<td>x<td>x<td>x<td>x<td>x<td>BaseSyntaxMaps
<tr><th>Pretty<td>x<td>x<td>x<td>x<td>x<td>x<td>x<td>BaseSyntaxPretty
<tr><th>Util<td>x<td>x<td>-<td>x<td>x<td>x<td>x<td>BaseSyntaxUtil
<tr><th>collected<td>HsDecl<td>HsExp<td>HsFields<td>HsGuards<td>HsKind<td>HsPat<td>HsType<td>BaseSyntax
</table>

<p>
There is also a small number of auxiliary modules.
<p>
The modules in the row and column marked <em>collected</em> just import
and reexport the modules in the respective row or column. The module
<code>BaseSyntax</code> exports everything defined in this directory.
<p>
The modules in the first row (Struct) define the data types and
are self-contained: they do not depend
on any other modules (except some types from the Haskell 98 Prelude).

<p>
The modules in the second row (Maps) define the three operations acc, map
and seq. These modules depend on the modules in the first row
(mostly the ones directly above)
and some auxiliary modules (AccList and MUtils, available in ../lib),
which in turn depend on some Haskell 98 Standrad Library Modules (List and
Monad).

<p>
The modules in the third row (Pretty) define instances in a pretty printing
class, and some auxiliary pretty printing functions.
They depend on a pretty printing library, which is provided in ../pretty,
modules on rows above, and in some cases, modules in the Util row.

<p>
The modules in the fourth row (Util) are more ad-hoc...
<p>
The modules in the last row are not used anymore...