diff --git a/GenI.cabal b/GenI.cabal --- a/GenI.cabal +++ b/GenI.cabal @@ -1,5 +1,5 @@ Name: GenI -Version: 0.24.2 +Version: 0.24.3 License: GPL License-file: LICENSE Author: Carlos Areces and Eric Kow @@ -10,7 +10,7 @@ Maintainer: geni-users@loria.fr Build-Type: Simple Cabal-Version: >=1.14 -data-files: AUTHORS, README.markdown, NEWS, GenI.cabal, +data-files: AUTHORS, README.markdown, changelog, GenI.cabal, examples/artificial/lexicon, examples/artificial/trees, examples/artificial/suite, diff --git a/NEWS b/NEWS deleted file mode 100644 --- a/NEWS +++ /dev/null @@ -1,220 +0,0 @@ -GenI 0.24, 18 Sep 2013 ----------------------- -Note that the changes between this release and 0.20 are considered to be under -the BSD3 license. GenI overall remains dual-licensed under the GPL and any -commercial-use terms you may wish to negotiate with INRIA. Having secured the -rights to use GenI 0.20, you may freely use GenI 0.24 in a similar fashion. - -CHANGES TO WATCH OUT FOR - -* Server/GUI changes: Semantic input must be full input. - - Before: `foo(x) bar(y z)` - - After: `semantics:[foo(x) bar(y z)]` -* Customisable semantics : now you can accept any arbitrary - input for which you can define a mapping to a GenI-style test case -* API change: the custom semantics argument is mandatory -* More extensive documentation - -GUI - -* Visual distinction between explicit null adjunction constraints - (marked NA) and constraints inserted by GenI (marked INA) -* Bugfixes (now retains show-feature state across debugger steps) -* More informative top/bot unification failure diagnostics in the - trash - -GENERAL - -* New "guided realisation" optimisation (focus on one polarity - path at a time) -* Fixed errors where top/bottom unification wasn't being done -* Builds with haskell-platform 2013.2.0.0 - -GenI 0.22, 14 Apr 2012 ----------------------- -Note that the changes between this release and 0.20 are considered to be under -the BSD3 license. GenI overall remains dual-licensed under the GPL and any -commercial-use terms you may wish to negotiate with INRIA. Having secured the -rights to use GenI 0.20, you may freely use GenI 0.22 in a similar fashion. - -CHANGES TO WATCH OUT FOR - -* Separation of geni and geni-gui into two packages; - simpler installation -* Now using the top feature for lemanchors instead of bot -* Empty disjunctions forbidden in unification variables -* JSON input/output to morph processors have changed -* Lexical selection unifies semantics of tree schema + lemma with - input semantics. - -GUI - -* New results tab with reminder of inputs -* Add gui element to display unanchored lexical selection. -* Jump to new tab in debugger panel when created. -* Update gui to use Pretty instead of Show -* Rename $algo-session tab to "tree assembly" -* Make warnings resizable. -* Fix display of path equations with 'interface' in them. -* Fix #50 - load button has no effect. -* Fix #49 - correct order that leaf nodes are returned. -* Show GenI version in About box. -* Add detect polarities and root feature editor to main gui. - -DOCUMENTATION - -* Literate GenI and genimanual replaced with - http://projects.haskell.org/GenI/manual - -GENERAL - -* Builds with GHC 7 -* Core behaviour - * Early null-adjunction and semfilter obligatory - * Handling of zero-literal semantic items restored - * Unconstrained polarities in automaton construction. - This makes it possible to do polarity detection with only a - weakly specified root feature like [cat:_], and without needing - the relevant feature to be implemented everywhere. - -* Flags: - * --trees (used to be --macros; latter is deprecated) - * --batchdir now optional (defaults to a new temp dir) - * --maxsteps (stop after N steps) - * --extrapol REMOVED (use root feature instead) -* Logging facility (not used much in GenI yet) - Can be configured in ~/.geni/config.yaml, for example - logging: - - - name : NLP.GenI.Console - level : WARN - format : simple "$msg" - - - name : NLP.Geni.LexicalSelection - level : DEBUG - format : simple "$utcTime $loggername $msg" - handler : stderr -* Less repetition in warnings (hopefully easier to read) -* More hiding of constructors for safety -* New enrichment option for setting co-anchors (foo.lex=hello) -* Lexical selection performance enhancements -* Variables that only occur once are converted to anonymous, - should make unification a bit more efficient -* Fix #39: reject malformed root feature input. -* New feature: - * Variables with constraints on their possible values (?X/foo|bar) - * Fancy disjunctions: tree schemata now allow disjunctions of - unification variables (but not recursive). These must flatten down - to plain old atomic disjunction once converted to elementary trees - -* Time metric in statistics (Laura Perez) -* Do top/bottom unification on na-constrained nodes during initialisation. -* Polarity detection relaxed to work with constrained variables too. - (?X/foo|bar gives the result as foo|bar) -* Bugfix in interpretation of root feature (it should be sorted). -* Flags: - * --rootfeat always assumed, but defaults to '[cat:_]' - * '-r' a short command line option for '--rootfeat'. - -LIBRARY - -* Somewhat safer and easier to understand API - (still no stability yet) -* Replace String with Text in GeniVal -* Replace Show abuse with custom Pretty class -* Slightly less stateful (no target semantics in state) -* Much rearranging and renaming (sorry!) -* New: ability to provide custom lexical selection action -* New: ability to provide custom morph postprocessing action -* de-haskell98 (Gwern Branwen) -* No more null builder. - -TOOLS (darcs get --lazy http://code.haskell.org/GenI) - -* new tool, genireport: summarise batch generation results -* geniserver now talks over HTTP using a JSON format -* Use Sylvain Salvati's xmg2geni.xsl instead of geniconvert. - * xmg2geni: fix treatment of missing lexemes. - * xmg2geni: treat type=coanchor as other nodes in GenI. -* geniwrapper: illustrates C wrapper of GenI API - -GenI 0.20, 29 Sep 2009 ----------------------- -- NON BACKWARD-COMPATIBLE CHANGES - - * GHC 6.8 or higher now required (GHC 6.10 + Haskell Platform preferred) - * Input files now *assumed* to be UTF-8 encoded - (output still ISO8859-1; hopefully locale-based in GHC 6.12) - * Interface between GenI and morphological realiser now uses a JSON format. - * Rootfeat optimisation now mandatory (flag no longer recognised) - -- NEW FUNCTIONALITY - - * new flag --version now works and reports version from Cabal file - * new flag --dump dumps derivation output to stdout in JSON format - * new flag --ranking foo ranks outputs according to OT-style constraints expressed in foo - * --batchdir now works with --testcase - * --batchdir now dumps derivations and statistics in JSON format - * --batchdir now works with instructions files - * --metrics always expands 'default' to the default metrics - (in addition to any other statistics you request) - * new optimisation: early null-adjunction detection - -- QUALITY ASSURANCE - - * Reference manual in docs/genimanual.pdf (make docs) - * cabal install -fgui and cabal install produce the same underlying library - only the executable is different - * Easier GUI installation for MacOS X (application bundles now built - automatically; no manual intervention required) - * Adopted odd/even convention to distinguish devel builds from stable ones - (eg. GenI 0.21.x is devel whereas GenI 0.20.x is stable) - -GenI 0.17.4, 6 Apr 2009 ------------------------ -* GHC 6.6 support - -* GUI disabled by default - -GenI 0.17.3, 3 Apr 2009 ------------------------ -* Simplified build method - * one single cabal package instead of two - * cabal configure -f-gui to disable GUI - * makefile stripped out - -* Lexical selection on empty semantics now allowed - * This is so that the zero-literal semantics mechanism can work again - -* Better help text - -* Baked-in unit testing (geni --unit-test) - -GenI 0.10, 11 Dec 2006 ----------------------- -* Performance much improved after Haskell profiling -* Pre-compiled grammars option, geniserver (buggy) - -GenI 0.9, 8 Dec 2006 --------------------- -* Switched to new syntax: variables now must be prefixed with '?' -* Switched from Alex/Happy to Parsec -* Added API documentation via haddock - -GenI 0.8, 16 Sep 2005 ---------------------- -* Support for latin-1 characters using Unicode wxhaskell -* Added a configure script and an install target in Makefile -* Changed from use of configuration files to use of command line switches -* Full configuration GUI -* Implementation of atomic disjunction -* --ignore-semantics mode (Jackie Lai) - -GenI 0.7, 8 June 2005 ---------------------- -* Upgraded to ghc 6.4, wxwidgets 2.6, wxhaskell 0.9.4 - -GenI 0.6, 3 May 2005 ---------------------- -* User interface fixes (Window size bugs) -* Interface with Yannick Parmientier's selection module diff --git a/README.markdown b/README.markdown --- a/README.markdown +++ b/README.markdown @@ -22,13 +22,13 @@ 2. Install the basic version first. If you just want the last stable release of GenI, - cabal install GenI geniserver + cabal install GenI geniserver geni-util However, if you want to install the unstable version from source, change to the directory this README is in and - cabal install . ./geniserver + cabal install . ./geniserver ./geni-util ## Graphical interface diff --git a/changelog b/changelog new file mode 100644 --- /dev/null +++ b/changelog @@ -0,0 +1,236 @@ +GenI 0.24.3 15 Nov 2013 +----------------------- +BUGFIXES: + +* Lexical selection: trees that fail enrichment due to unification failure are + now discarded + + Previously, there was some confusion over whether the expected behaviour was + for this to be an error or warning. The behaviour after this fix is that + missing nodes trigger a warning, an unification failures trigger an error + (discarded tree) + +* Realisation: When anonymising singleton variables, GenI preserves their + constraints. This should fix some subtle overgeneration problems that may + arise in automatically generated grammars + +GenI 0.24, 18 Sep 2013 +---------------------- +Note that the changes between this release and 0.20 are considered to be under +the BSD3 license. GenI overall remains dual-licensed under the GPL and any +commercial-use terms you may wish to negotiate with INRIA. Having secured the +rights to use GenI 0.20, you may freely use GenI 0.24 in a similar fashion. + +CHANGES TO WATCH OUT FOR + +* Server/GUI changes: Semantic input must be full input. + - Before: `foo(x) bar(y z)` + - After: `semantics:[foo(x) bar(y z)]` +* Customisable semantics : now you can accept any arbitrary + input for which you can define a mapping to a GenI-style test case +* API change: the custom semantics argument is mandatory +* More extensive documentation + +GUI + +* Visual distinction between explicit null adjunction constraints + (marked NA) and constraints inserted by GenI (marked INA) +* Bugfixes (now retains show-feature state across debugger steps) +* More informative top/bot unification failure diagnostics in the + trash + +GENERAL + +* New "guided realisation" optimisation (focus on one polarity + path at a time) +* Fixed errors where top/bottom unification wasn't being done +* Builds with haskell-platform 2013.2.0.0 + +GenI 0.22, 14 Apr 2012 +---------------------- +Note that the changes between this release and 0.20 are considered to be under +the BSD3 license. GenI overall remains dual-licensed under the GPL and any +commercial-use terms you may wish to negotiate with INRIA. Having secured the +rights to use GenI 0.20, you may freely use GenI 0.22 in a similar fashion. + +CHANGES TO WATCH OUT FOR + +* Separation of geni and geni-gui into two packages; + simpler installation +* Now using the top feature for lemanchors instead of bot +* Empty disjunctions forbidden in unification variables +* JSON input/output to morph processors have changed +* Lexical selection unifies semantics of tree schema + lemma with + input semantics. + +GUI + +* New results tab with reminder of inputs +* Add gui element to display unanchored lexical selection. +* Jump to new tab in debugger panel when created. +* Update gui to use Pretty instead of Show +* Rename $algo-session tab to "tree assembly" +* Make warnings resizable. +* Fix display of path equations with 'interface' in them. +* Fix #50 - load button has no effect. +* Fix #49 - correct order that leaf nodes are returned. +* Show GenI version in About box. +* Add detect polarities and root feature editor to main gui. + +DOCUMENTATION + +* Literate GenI and genimanual replaced with + http://projects.haskell.org/GenI/manual + +GENERAL + +* Builds with GHC 7 +* Core behaviour + * Early null-adjunction and semfilter obligatory + * Handling of zero-literal semantic items restored + * Unconstrained polarities in automaton construction. + This makes it possible to do polarity detection with only a + weakly specified root feature like [cat:_], and without needing + the relevant feature to be implemented everywhere. + +* Flags: + * --trees (used to be --macros; latter is deprecated) + * --batchdir now optional (defaults to a new temp dir) + * --maxsteps (stop after N steps) + * --extrapol REMOVED (use root feature instead) +* Logging facility (not used much in GenI yet) + Can be configured in ~/.geni/config.yaml, for example + logging: + - + name : NLP.GenI.Console + level : WARN + format : simple "$msg" + - + name : NLP.Geni.LexicalSelection + level : DEBUG + format : simple "$utcTime $loggername $msg" + handler : stderr +* Less repetition in warnings (hopefully easier to read) +* More hiding of constructors for safety +* New enrichment option for setting co-anchors (foo.lex=hello) +* Lexical selection performance enhancements +* Variables that only occur once are converted to anonymous, + should make unification a bit more efficient +* Fix #39: reject malformed root feature input. +* New feature: + * Variables with constraints on their possible values (?X/foo|bar) + * Fancy disjunctions: tree schemata now allow disjunctions of + unification variables (but not recursive). These must flatten down + to plain old atomic disjunction once converted to elementary trees + +* Time metric in statistics (Laura Perez) +* Do top/bottom unification on na-constrained nodes during initialisation. +* Polarity detection relaxed to work with constrained variables too. + (?X/foo|bar gives the result as foo|bar) +* Bugfix in interpretation of root feature (it should be sorted). +* Flags: + * --rootfeat always assumed, but defaults to '[cat:_]' + * '-r' a short command line option for '--rootfeat'. + +LIBRARY + +* Somewhat safer and easier to understand API + (still no stability yet) +* Replace String with Text in GeniVal +* Replace Show abuse with custom Pretty class +* Slightly less stateful (no target semantics in state) +* Much rearranging and renaming (sorry!) +* New: ability to provide custom lexical selection action +* New: ability to provide custom morph postprocessing action +* de-haskell98 (Gwern Branwen) +* No more null builder. + +TOOLS (darcs get --lazy http://code.haskell.org/GenI) + +* new tool, genireport: summarise batch generation results +* geniserver now talks over HTTP using a JSON format +* Use Sylvain Salvati's xmg2geni.xsl instead of geniconvert. + * xmg2geni: fix treatment of missing lexemes. + * xmg2geni: treat type=coanchor as other nodes in GenI. +* geniwrapper: illustrates C wrapper of GenI API + +GenI 0.20, 29 Sep 2009 +---------------------- +- NON BACKWARD-COMPATIBLE CHANGES + + * GHC 6.8 or higher now required (GHC 6.10 + Haskell Platform preferred) + * Input files now *assumed* to be UTF-8 encoded + (output still ISO8859-1; hopefully locale-based in GHC 6.12) + * Interface between GenI and morphological realiser now uses a JSON format. + * Rootfeat optimisation now mandatory (flag no longer recognised) + +- NEW FUNCTIONALITY + + * new flag --version now works and reports version from Cabal file + * new flag --dump dumps derivation output to stdout in JSON format + * new flag --ranking foo ranks outputs according to OT-style constraints expressed in foo + * --batchdir now works with --testcase + * --batchdir now dumps derivations and statistics in JSON format + * --batchdir now works with instructions files + * --metrics always expands 'default' to the default metrics + (in addition to any other statistics you request) + * new optimisation: early null-adjunction detection + +- QUALITY ASSURANCE + + * Reference manual in docs/genimanual.pdf (make docs) + * cabal install -fgui and cabal install produce the same underlying library + only the executable is different + * Easier GUI installation for MacOS X (application bundles now built + automatically; no manual intervention required) + * Adopted odd/even convention to distinguish devel builds from stable ones + (eg. GenI 0.21.x is devel whereas GenI 0.20.x is stable) + +GenI 0.17.4, 6 Apr 2009 +----------------------- +* GHC 6.6 support + +* GUI disabled by default + +GenI 0.17.3, 3 Apr 2009 +----------------------- +* Simplified build method + * one single cabal package instead of two + * cabal configure -f-gui to disable GUI + * makefile stripped out + +* Lexical selection on empty semantics now allowed + * This is so that the zero-literal semantics mechanism can work again + +* Better help text + +* Baked-in unit testing (geni --unit-test) + +GenI 0.10, 11 Dec 2006 +---------------------- +* Performance much improved after Haskell profiling +* Pre-compiled grammars option, geniserver (buggy) + +GenI 0.9, 8 Dec 2006 +-------------------- +* Switched to new syntax: variables now must be prefixed with '?' +* Switched from Alex/Happy to Parsec +* Added API documentation via haddock + +GenI 0.8, 16 Sep 2005 +--------------------- +* Support for latin-1 characters using Unicode wxhaskell +* Added a configure script and an install target in Makefile +* Changed from use of configuration files to use of command line switches +* Full configuration GUI +* Implementation of atomic disjunction +* --ignore-semantics mode (Jackie Lai) + +GenI 0.7, 8 June 2005 +--------------------- +* Upgraded to ghc 6.4, wxwidgets 2.6, wxhaskell 0.9.4 + +GenI 0.6, 3 May 2005 +--------------------- +* User interface fixes (Window size bugs) +* Interface with Yannick Parmientier's selection module diff --git a/examples/artificial/lexicon b/examples/artificial/lexicon --- a/examples/artificial/lexicon +++ b/examples/artificial/lexicon @@ -67,3 +67,22 @@ trace-good tr-good () semantics:[trace()] trace-bad tr-bad () semantics:[trace()] + +enrichment-good enrichment () +equations:[anchor.bot.foo:+] +semantics:[enrichment-good()] + +enrichment-bad enrichment () +equations:[anchor.bot.foo:-] +semantics:[enrichment-bad()] + +enrichment-restraint-good enrichment-restraint () +equations:[anchor.bot.foo:+] +semantics:[enrichment-restraint-good()] + +enrichment-missing-node-good enrichment () +equations:[foo.bot.foo:+] +semantics:[enrichment-missing-node-good()] + +single-user-var single-use-var () +semantics:[single-use-var()] diff --git a/examples/artificial/suite b/examples/artificial/suite --- a/examples/artificial/suite +++ b/examples/artificial/suite @@ -34,3 +34,12 @@ variablecat semantics:[variablecat()] trace-good semantics:[trace()[T1]] + +enrichment-good +semantics:[enrichment-good()] + +enrichment-restraint-good +semantics:[enrichment-restraint-good()] + +enrichment-missing-node-good +semantics:[enrichment-missing-node-good()] diff --git a/examples/artificial/suite-bad b/examples/artificial/suite-bad --- a/examples/artificial/suite-bad +++ b/examples/artificial/suite-bad @@ -14,3 +14,8 @@ interface-unification semantics:[interface()] trace-bad semantics:[trace()[T2]] + +enrichment-bad semantics:[enrichment-bad()] + +single-use-var +semantics:[single-use-var()] diff --git a/examples/artificial/trees b/examples/artificial/trees --- a/examples/artificial/trees +++ b/examples/artificial/trees @@ -158,3 +158,16 @@ tr-bad() initial X anchor [cat:x]![cat:y] trace:[T2] + +enrichment() initial +X anchor [cat:x]![foo:+] + +enrichment-restraint:e1() initial % meant to fail +X anchor [cat:x]![foo:-] + +enrichment-restraint:e2() initial % meant to be left behind +X anchor [cat:x]![] + +% should not be anonymised away +single-use-var() initial +X anchor [cat:x]![cat:?X/y] diff --git a/src/NLP/GenI/GeniVal/Internal.hs b/src/NLP/GenI/GeniVal/Internal.hs --- a/src/NLP/GenI/GeniVal/Internal.hs +++ b/src/NLP/GenI/GeniVal/Internal.hs @@ -386,12 +386,18 @@ -- | Anonymise any variable that occurs only once in the object anonymiseSingletons :: (Collectable a, DescendGeniVal a) => a -> a anonymiseSingletons x = - replace subst x + descendGeniVal anonymiseIfLonely x where - subst = Map.map (const mkGAnon) . Map.filter (== 1) - -- merge counts for same var, different constraints - . Map.fromListWith (+) . map (first fst) . Map.toList - $ collect x Map.empty + anonymiseIfLonely v = + case gLabel v of + Just l | l `elem` lonely -> anonymise v + _ -> v + anonymise v = v { gLabel = Nothing } + lonely = Map.keys + . Map.filter (== 1) + -- merge counts for same var, different constraints + . Map.fromListWith (+) . map (first fst) . Map.toList + $ collect x Map.empty -- | 'finaliseVarsById' appends a unique suffix to all variables in -- an object. This avoids us having to alpha convert all the time diff --git a/src/NLP/GenI/LexicalSelection.hs b/src/NLP/GenI/LexicalSelection.hs --- a/src/NLP/GenI/LexicalSelection.hs +++ b/src/NLP/GenI/LexicalSelection.hs @@ -307,7 +307,7 @@ -- ** Enrichment -- ---------------------------------------------------------------------- --- | See +-- | See -- on enrichement enrich :: LexEntry -> SchemaTree -> LexCombine SchemaTree enrich l t = do @@ -327,39 +327,46 @@ -- *** 'enrich' helpers +data EnrichmentResult = EnrSuccess SchemaTree Subst + | EnrNotFound + | EnrFailed + -- | Helper for 'enrich' (enrich by single path equation) enrichBy :: SchemaTree -> PathEqPair -> LexCombine SchemaTree enrichBy t eq@(eqLhs, _) = case maybeEnrichBy t eq of - Nothing -> lexTell enrichErr >> return t - Just (t2,_) -> return t2 + EnrNotFound -> return t -- warning generated separately :-( + EnrFailed -> lexTell enrichErr >> mzero + EnrSuccess t2 _ -> return t2 where - enrichErr = SchemaError [pidname t] (EnrichError (PeqJust eqLhs)) + enrichErr = SchemaError [pidname t] $ + EnrichError (PeqJust eqLhs) -- | Helper for 'enrichBy' maybeEnrichBy :: SchemaTree -> PathEqPair - -> Maybe (SchemaTree, Subst) -maybeEnrichBy t (eqLhs, eqVal) = do - node <- seekCoanchor eqLhs t - case eqLhs of - PeqFeat _ eqTop eqAtt -> do - let (get, set) = case eqTop of - Top -> (gup, \n x -> n { gup = x }) - Bottom -> (gdown, \n x -> n { gdown = x}) - (fs, sub) <- hush $ enrichFeat (AvPair eqAtt eqVal) (get node) - let t2 = fixNode (set node fs) (replace sub t) - return (t2, sub) - PeqLex _ -> do - vs <- gConstraints eqVal - let node2 = node { glexeme = FL.fromFL vs } - t2 = fixNode node2 t - return (t2, Map.empty) + -> EnrichmentResult +maybeEnrichBy t (eqLhs, eqVal) = + maybe EnrNotFound enrichNode $ seekCoanchor eqLhs t where fixNode n mt = mt { tree = repNodeByNode (matchNodeName eqLhs) n (tree mt) } + enrichNode node = fromMaybe EnrFailed $ + case eqLhs of + PeqFeat _ eqTop eqAtt -> do + let (get, set) = case eqTop of + Top -> (gup, \n x -> n { gup = x }) + Bottom -> (gdown, \n x -> n { gdown = x}) + (fs, sub) <- hush $ enrichFeat (AvPair eqAtt eqVal) (get node) + let t2 = fixNode (set node fs) (replace sub t) + return $ EnrSuccess t2 sub + PeqLex _ -> do + vs <- gConstraints eqVal + let node2 = node { glexeme = FL.fromFL vs } + t2 = fixNode node2 t + return $ EnrSuccess t2 Map.empty -- | @enrichFeat av fs@ attempts to unify @av@ with @fs@ -- diff --git a/src/NLP/GenI/LexicalSelection/Types.hs b/src/NLP/GenI/LexicalSelection/Types.hs --- a/src/NLP/GenI/LexicalSelection/Types.hs +++ b/src/NLP/GenI/LexicalSelection/Types.hs @@ -99,7 +99,7 @@ | SchemaError [Text] LexCombineError2 deriving Eq -data LexCombineError2 = EnrichError PathEqLhs +data LexCombineError2 = EnrichError PathEqLhs | StringError Text deriving (Eq, Ord) @@ -111,10 +111,10 @@ leq _ _ = False instance Poset LexCombineError2 where - leq (EnrichError e1) (EnrichError e2) = leq e1 e2 - leq (EnrichError _ ) (StringError _ ) = True - leq (StringError s1) (StringError s2) = leq s1 s2 - leq _ _ = False + leq (EnrichError e1) (EnrichError e2) = leq e1 e2 + leq (EnrichError _ ) (StringError _ ) = True + leq (StringError s1) (StringError s2) = leq s1 s2 + leq _ _ = False instance Poset PathEqLhs where leq l1 l2 = leq (showPathEqLhs l1) (showPathEqLhs l2)