From: simonpj@microsoft.com Date: Wed, 22 Aug 2007 15:41:46 +0000 (+0000) Subject: Add comments about ModGuts instance envts (and re-order fields) X-Git-Url: http://git.megacz.com/?a=commitdiff_plain;h=9c6bd70dc4f1a51a487790c7218d9648783c4e70;p=ghc-hetmet.git Add comments about ModGuts instance envts (and re-order fields) --- diff --git a/compiler/main/HscTypes.lhs b/compiler/main/HscTypes.lhs index c1882d6..acb47c5 100644 --- a/compiler/main/HscTypes.lhs +++ b/compiler/main/HscTypes.lhs @@ -522,16 +522,9 @@ data ModGuts mg_usages :: ![Usage], -- Version info for what it needed mg_rdr_env :: !GlobalRdrEnv, -- Top-level lexical environment - mg_fix_env :: !FixityEnv, -- Fixity env, for things declared in - -- this module - - mg_inst_env :: InstEnv, -- Class instance enviroment fro - -- *home-package* modules (including - -- this one); c.f. tcg_inst_env - mg_fam_inst_env :: FamInstEnv, -- Type-family instance enviroment - -- for *home-package* modules (including - -- this one); c.f. tcg_fam_inst_env + -- These fields all describe the things **declared in this module** + mg_fix_env :: !FixityEnv, -- Fixities mg_types :: !TypeEnv, mg_insts :: ![Instance], -- Instances mg_fam_insts :: ![FamInst], -- Instances @@ -541,7 +534,19 @@ data ModGuts mg_deprecs :: !Deprecations, -- Deprecations declared in the module mg_hpc_info :: !HpcInfo, -- info about coverage tick boxes mg_modBreaks :: !ModBreaks, - mg_vect_info :: !VectInfo -- Pool of vectorised declarations + mg_vect_info :: !VectInfo, -- Pool of vectorised declarations + + -- The next two fields are unusual, because they give instance + -- environments for *all* modules in the home package, including + -- this module, rather than for *just* this module. + -- Reason: when looking up an instance we don't want to have to + -- look at each module in the home package in turn + mg_inst_env :: InstEnv, -- Class instance enviroment fro + -- *home-package* modules (including + -- this one); c.f. tcg_inst_env + mg_fam_inst_env :: FamInstEnv -- Type-family instance enviroment + -- for *home-package* modules (including + -- this one); c.f. tcg_fam_inst_env } -- The ModGuts takes on several slightly different forms: