Commit e0955d95 authored by simonm's avatar simonm
Browse files

[project @ 1999-04-27 15:20:20 by simonm]

deriving fixes.
parent bb341c45
......@@ -211,7 +211,7 @@ tcDeriving modname fixs rn_name_supply inst_decl_infos_in
-- Now augment the InstInfos, adding in the rather boring
-- actual-code-to-do-the-methods binds. We may also need to
-- generate extra not-one-inst-decl-specific binds, notably
-- the "con2tag" function. We do these
-- "con2tag" and/or "tag2con" functions. We do these
-- separately.
gen_taggery_Names new_inst_infos `thenTc` \ nm_alist_etc ->
......@@ -539,6 +539,10 @@ these is around is given by @hasCon2TagFun@.
The examples under the different sections below will make this
clearer.
\item
Much less often (really just for deriving @Ix@), we use a
@_tag2con_<tycon>@ function. See the examples.
\item
We use the renamer!!! Reason: we're supposed to be
producing @RenamedMonoBinds@ for the methods, but that means
......@@ -601,7 +605,7 @@ gen_inst_info modname
%************************************************************************
%* *
\subsection[TcDeriv-taggery-Names]{What con2tag functions are available?}
\subsection[TcDeriv-taggery-Names]{What con2tag/tag2con functions are available?}
%* *
%************************************************************************
......@@ -609,6 +613,7 @@ gen_inst_info modname
data Foo ... = ...
con2tag_Foo :: Foo ... -> Int#
tag2con_Foo :: Int -> Foo ... -- easier if Int, not Int#
maxtag_Foo :: Int -- ditto (NB: not unboxed)
......@@ -622,6 +627,14 @@ Or: we're deriving @Ord@ (unless single-constructor), @Enum@, @Ix@
(enum type only????)
\end{itemize}
We have a @tag2con@ function for a tycon if:
\begin{itemize}
\item
We're deriving @Enum@, or @Ix@ (enum type only???)
\end{itemize}
If we have a @tag2con@ function, we also generate a @maxtag@ constant.
\begin{code}
gen_taggery_Names :: [InstInfo]
-> TcM s [(RdrName, -- for an assoc list
......@@ -631,7 +644,7 @@ gen_taggery_Names :: [InstInfo]
gen_taggery_Names inst_infos
= --pprTrace "gen_taggery:\n" (vcat [hsep [ppr c, ppr t] | (c,t) <- all_CTs]) $
foldlTc do_con2tag [] tycons_of_interest `thenTc` \ names_so_far ->
foldlTc do_maxtag names_so_far tycons_of_interest
foldlTc do_tag2con names_so_far tycons_of_interest
where
all_CTs = [ (c, get_tycon ty) | (InstInfo c _ [ty] _ _ _ _ _) <- inst_infos ]
......@@ -654,11 +667,12 @@ gen_taggery_Names inst_infos
| otherwise
= returnTc acc_Names
do_maxtag acc_Names tycon
do_tag2con acc_Names tycon
| isDataTyCon tycon &&
(we_are_deriving enumClassKey tycon ||
we_are_deriving ixClassKey tycon)
= returnTc ( (maxtag_RDR tycon, tycon, GenMaxTag)
= returnTc ( (tag2con_RDR tycon, tycon, GenTag2Con)
: (maxtag_RDR tycon, tycon, GenMaxTag)
: acc_Names)
| otherwise
= returnTc acc_Names
......
......@@ -28,7 +28,7 @@ module TcGenDeriv (
import HsSyn ( InPat(..), HsExpr(..), MonoBinds(..),
Match(..), GRHSs(..), Stmt(..), HsLit(..),
HsBinds(..), StmtCtxt(..),
HsBinds(..), StmtCtxt(..), HsType(..),
unguardedRHS, mkSimpleMatch
)
import RdrHsSyn ( mkOpApp, RdrNameMonoBinds, RdrNameHsExpr, RdrNamePat )
......@@ -1083,7 +1083,9 @@ gen_tag_n_con_monobind (rdr_name, tycon, GenCon2Tag)
gen_tag_n_con_monobind (rdr_name, tycon, GenTag2Con)
= mk_FunMonoBind (getSrcLoc tycon) rdr_name
([([VarPatIn a_RDR], HsApp tagToEnum_Expr a_Expr)])
[([ConPatIn mkInt_RDR [VarPatIn a_RDR]],
ExprWithTySig (HsApp tagToEnum_Expr a_Expr)
(MonoTyVar (qual_orig_name tycon)))]
gen_tag_n_con_monobind (rdr_name, tycon, GenMaxTag)
= mk_easy_FunMonoBind (getSrcLoc tycon)
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment