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
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: