Changes between Version 6 and Version 7 of ExternalCore

Timestamp:

11/07/06 12:08:21 (7 years ago)

Author:

guest

Comment:

--

ExternalCore

@@ -3 +3 @@
 The {{{ExternalCore}}} data type is used by GHC to communicate code represented in the [wiki:Commentary/Compiler/CoreSynType Core] data type with the outside world. It comes with an external syntax, a parser, a pretty printer, and code to convert between Core and External Core. Unfortunately, External Core has not been widely used, and the code has bit-rotted. The recent changes in Core to use [wiki:Commentary/Compiler/FC System FC] have exacerbated the problem. This page documents the process of getting External Core and Core back in sync.
 
+Once the process is finished, this page will just describe the design.
 
 == Relevant files ==
@@ -25 +26 @@
   * [http://www.haskell.org/ghc/docs/latest/html/users_guide/ext-core.html]: What the User's Guide currently has to say about External Core.
 
-== Design decisions ==
+== Design changes ==
 
-  * Probably want to represent all data types as GADTs, even if they can be represented in Haskell 98 form, so that we only have one representation.
-  * TODO: more!
+  * External Core originally parsed into a list of {{{TyClDecl}}} and a list of {{{IfaceBinding}}}. It now seems as though it might be better to replace the {{{IfaceBinding}}} with {{{LHsDecl}}}. This would require us to:
+    * Add a new data constructor for {{{HsBind}}}: {{{data HsBind id = ... | CoreBind id (ExtCore id)}}}
+    * Extend the renamer to rename {{{ExtCore RdrName}}} to {{{ExtCore Name}}}
+    * Extend the type checker to typecheck {{{ExtCore Name}}} to generate {{{ExtCore Id}}}
+    * Extend the desugarer to desugar {{{ExtCore Id}}} to {{{Core}}}
+  * We probably want to represent all data types as GADTs, even if they can be represented in Haskell 98 form, so that we only have one representation.
 
 == Tasks ==
 
-  * Define an external text representation for External Core (which will probably be simply a minor modification of the old format)
+  * Define an external text representation for External Core (which will probably be simply a minor modification of the old format) (mostly  done?)
   * Update the External Core data type to be compatible with the current Core data type. (mostly done)
   * Update {{{PprExternalCore.lhs}}} to print stuff that {{{LexCore}}} and {{{ParserCore}}} can understand. (mostly done)
   * Update {{{MkExternalCore.lhs}}} to support both the current Core and the new External Core. (mostly done)
-  * Update {{{LexCore.hs}}}, {{{ParserCore.y}}}, and {{{ParserCoreUtils.hs}}} to support the new data type and external syntax.
+  * Update the parser to recognize the new external syntax, generating an empty module at first. (partly done)
+  * Update the parser to generate LHsBind rather than IfaceBinding
   * Convert the current External Core documentation (in LaTeX) into a chapter (in XML) in the User's Guide.
-
-== Naming issues ==
-
-Since External Core was introduced, the {{{IfaceSyn}}} data type has changed. Originally (including in 6.6), it represented external name references using {{{IfaceExtName}}}. Now (in Darcs HEAD), it uses {{{Name}}} instead. This change leaves the External Core parser with the responsibility of generating a {{{Unique}}} for each name it encounters.
 
 == Miscellaneous notes ==