2 % (c) The University of Glasgow 2006
3 % (c) The AQUA Project, Glasgow University, 1996-1998
6 Printing of Core syntax
10 pprCoreExpr, pprParendExpr,
11 pprCoreBinding, pprCoreBindings, pprCoreAlt,
37 %************************************************************************
39 \subsection{Public interfaces for Core printing (excluding instances)}
41 %************************************************************************
43 @pprParendCoreExpr@ puts parens around non-atomic Core expressions.
46 pprCoreBindings :: OutputableBndr b => [Bind b] -> SDoc
47 pprCoreBinding :: OutputableBndr b => Bind b -> SDoc
48 pprCoreExpr :: OutputableBndr b => Expr b -> SDoc
49 pprParendExpr :: OutputableBndr b => Expr b -> SDoc
51 pprCoreBindings = pprTopBinds
52 pprCoreBinding = pprTopBind
54 instance OutputableBndr b => Outputable (Bind b) where
55 ppr bind = ppr_bind bind
57 instance OutputableBndr b => Outputable (Expr b) where
58 ppr expr = pprCoreExpr expr
62 %************************************************************************
66 %************************************************************************
69 pprTopBinds :: OutputableBndr a => [Bind a] -> SDoc
70 pprTopBinds binds = vcat (map pprTopBind binds)
72 pprTopBind :: OutputableBndr a => Bind a -> SDoc
73 pprTopBind (NonRec binder expr)
74 = ppr_binding (binder,expr) $$ blankLine
77 = ptext (sLit "Rec { }")
78 pprTopBind (Rec (b:bs))
79 = vcat [ptext (sLit "Rec {"),
81 vcat [blankLine $$ ppr_binding b | b <- bs],
82 ptext (sLit "end Rec }"),
87 ppr_bind :: OutputableBndr b => Bind b -> SDoc
89 ppr_bind (NonRec val_bdr expr) = ppr_binding (val_bdr, expr)
90 ppr_bind (Rec binds) = vcat (map pp binds)
92 pp bind = ppr_binding bind <> semi
94 ppr_binding :: OutputableBndr b => (b, Expr b) -> SDoc
95 ppr_binding (val_bdr, expr)
96 = pprBndr LetBind val_bdr $$
97 hang (ppr val_bdr <+> equals) 2 (pprCoreExpr expr)
101 pprParendExpr expr = ppr_expr parens expr
102 pprCoreExpr expr = ppr_expr noParens expr
104 noParens :: SDoc -> SDoc
109 ppr_expr :: OutputableBndr b => (SDoc -> SDoc) -> Expr b -> SDoc
110 -- The function adds parens in context that need
111 -- an atomic value (e.g. function args)
113 ppr_expr add_par (Type ty) = add_par (ptext (sLit "TYPE") <+> ppr ty) -- Wierd
115 ppr_expr _ (Var name) = ppr name
116 ppr_expr _ (Lit lit) = ppr lit
118 ppr_expr add_par (Cast expr co)
120 sep [pprParendExpr expr,
121 ptext (sLit "`cast`") <+> pprCo co]
123 pprCo co | opt_SuppressCoercions = ptext (sLit "...")
125 $ sep [ppr co, dcolon <+> ppr (coercionKindPredTy co)]
128 ppr_expr add_par expr@(Lam _ _)
130 (bndrs, body) = collectBinders expr
133 hang (ptext (sLit "\\") <+> sep (map (pprBndr LambdaBind) bndrs) <+> arrow)
136 ppr_expr add_par expr@(App {})
137 = case collectArgs expr of { (fun, args) ->
139 pp_args = sep (map pprArg args)
140 val_args = dropWhile isTypeArg args -- Drop the type arguments for tuples
141 pp_tup_args = sep (punctuate comma (map pprCoreExpr val_args))
144 Var f -> case isDataConWorkId_maybe f of
145 -- Notice that we print the *worker*
146 -- for tuples in paren'd format.
147 Just dc | saturated && isTupleTyCon tc
148 -> tupleParens (tupleTyConBoxity tc) pp_tup_args
151 saturated = val_args `lengthIs` idArity f
153 _ -> add_par (hang (ppr f) 2 pp_args)
155 _ -> add_par (hang (pprParendExpr fun) 2 pp_args)
158 ppr_expr add_par (Case expr var ty [(con,args,rhs)])
160 sep [sep [ptext (sLit "case") <+> pprCoreExpr expr,
161 ifPprDebug (braces (ppr ty)),
162 sep [ptext (sLit "of") <+> ppr_bndr var,
163 char '{' <+> ppr_case_pat con args]
169 ppr_bndr = pprBndr CaseBind
171 ppr_expr add_par (Case expr var ty alts)
173 sep [sep [ptext (sLit "case")
175 <+> ifPprDebug (braces (ppr ty)),
176 ptext (sLit "of") <+> ppr_bndr var <+> char '{'],
177 nest 2 (sep (punctuate semi (map pprCoreAlt alts))),
181 ppr_bndr = pprBndr CaseBind
184 -- special cases: let ... in let ...
185 -- ("disgusting" SLPJ)
188 ppr_expr add_par (Let bind@(NonRec val_bdr rhs@(Let _ _)) body)
191 hsep [ptext (sLit "let {"), (pprBndr LetBind val_bdr $$ ppr val_bndr), equals],
192 nest 2 (pprCoreExpr rhs),
196 ppr_expr add_par (Let bind@(NonRec val_bdr rhs) expr@(Let _ _))
198 (hang (ptext (sLit "let {"))
199 2 (hsep [ppr_binding (val_bdr,rhs),
200 ptext (sLit "} in")])
205 -- General case (recursive case, too)
206 ppr_expr add_par (Let bind expr)
208 sep [hang (ptext keyword) 2 (ppr_bind bind <+> ptext (sLit "} in")),
211 keyword = case bind of
212 Rec _ -> (sLit "letrec {")
213 NonRec _ _ -> (sLit "let {")
215 ppr_expr add_par (Note (SCC cc) expr)
216 = add_par (sep [pprCostCentreCore cc, pprCoreExpr expr])
218 ppr_expr add_par (Note InlineMe expr)
219 = add_par $ ptext (sLit "__inline_me") <+> pprParendExpr expr
221 ppr_expr add_par (Note (CoreNote s) expr)
223 sep [sep [ptext (sLit "__core_note"), pprHsString (mkFastString s)],
226 pprCoreAlt :: OutputableBndr a => (AltCon, [a] , Expr a) -> SDoc
227 pprCoreAlt (con, args, rhs)
228 = hang (ppr_case_pat con args) 2 (pprCoreExpr rhs)
230 ppr_case_pat :: OutputableBndr a => AltCon -> [a] -> SDoc
231 ppr_case_pat (DataAlt dc) args
233 = tupleParens (tupleTyConBoxity tc) (hsep (punctuate comma (map ppr_bndr args))) <+> arrow
235 ppr_bndr = pprBndr CaseBind
238 ppr_case_pat con args
239 = ppr con <+> sep (map ppr_bndr args) <+> arrow
241 ppr_bndr = pprBndr CaseBind
243 pprArg :: OutputableBndr a => Expr a -> SDoc
244 pprArg (Type ty) = ptext (sLit "@") <+> pprParendType ty
245 pprArg expr = pprParendExpr expr
248 Other printing bits-and-bobs used with the general @pprCoreBinding@
249 and @pprCoreExpr@ functions.
252 instance OutputableBndr Var where
253 pprBndr = pprCoreBinder
255 pprCoreBinder :: BindingSite -> Var -> SDoc
256 pprCoreBinder LetBind binder
257 | isTyVar binder = pprKindedTyVarBndr binder
259 = vcat [sig, pprIdExtras binder, pragmas]
261 sig = pprTypedBinder binder
262 pragmas = ppIdInfo binder (idInfo binder)
264 -- Lambda bound type variables are preceded by "@"
265 pprCoreBinder LambdaBind bndr
267 = getPprStyle $ \ sty ->
268 if debugStyle sty then
269 parens (pprTypedBinder bndr)
273 = parens (pprTypedBinder bndr)
275 -- Case bound things don't get a signature or a herald, unless we have debug on
276 pprCoreBinder CaseBind bndr
277 = getPprStyle $ \ sty ->
278 if debugStyle sty then
279 parens (pprTypedBinder bndr)
281 if isDeadBinder bndr then char '_'
282 else pprUntypedBinder bndr
284 pprUntypedBinder :: Var -> SDoc
285 pprUntypedBinder binder
286 | isTyVar binder = ptext (sLit "@") <+> ppr binder -- NB: don't print kind
287 | otherwise = pprIdBndr binder
289 pprTypedBinder :: Var -> SDoc
290 -- Print binder with a type or kind signature (not paren'd)
291 pprTypedBinder binder
292 | isTyVar binder = pprKindedTyVarBndr binder
293 | otherwise = pprIdBndr binder <+> dcolon <+> pprType (idType binder)
295 pprKindedTyVarBndr :: TyVar -> SDoc
296 -- Print a type variable binder with its kind (but not if *)
297 pprKindedTyVarBndr tyvar
298 = ptext (sLit "@") <+> ppr tyvar <> opt_kind
300 opt_kind -- Print the kind if not *
301 | isLiftedTypeKind kind = empty
302 | otherwise = dcolon <> pprKind kind
303 kind = tyVarKind tyvar
305 -- pprIdBndr does *not* print the type
306 -- When printing any Id binder in debug mode, we print its inline pragma and one-shot-ness
307 pprIdBndr :: Id -> SDoc
308 pprIdBndr id = ppr id <+> pprIdBndrInfo (idInfo id)
310 pprIdBndrInfo :: IdInfo -> SDoc
312 = megaSeqIdInfo info `seq` doc -- The seq is useful for poking on black holes
314 prag_info = inlinePragInfo info
315 occ_info = occInfo info
316 dmd_info = newDemandInfo info
317 lbv_info = lbvarInfo info
319 no_info = isDefaultInlinePragma prag_info && isNoOcc occ_info &&
320 (case dmd_info of { Nothing -> True; Just d -> isTop d }) &&
321 hasNoLBVarInfo lbv_info
323 doc | no_info = empty
325 = brackets $ hsep [ppr prag_info, ppr occ_info,
326 ppr dmd_info, ppr lbv_info
327 #ifdef OLD_STRICTNESS
328 , ppr (demandInfo id)
335 pprIdExtras :: Id -> SDoc
336 pprIdExtras id = pp_scope <> ppr (idDetails id)
338 pp_scope | isGlobalId id = ptext (sLit "GblId")
339 | isExportedId id = ptext (sLit "LclIdX")
340 | otherwise = ptext (sLit "LclId")
342 ppIdInfo :: Id -> IdInfo -> SDoc
345 vcat [ ppArityInfo a,
346 ppWorkerInfo (workerInfo info),
347 ppCafInfo (cafInfo info),
348 #ifdef OLD_STRICTNESS
352 pprNewStrictness (newStrictnessInfo info),
353 if null rules then empty
354 else ptext (sLit "RULES:") <+> vcat (map pprRule rules)
355 -- Inline pragma, occ, demand, lbvar info
356 -- printed out with all binders (when debug is on);
357 -- see PprCore.pprIdBndr
361 #ifdef OLD_STRICTNESS
362 s = strictnessInfo info
365 rules = specInfoRules (specInfo info)
370 instance Outputable CoreRule where
373 pprRules :: [CoreRule] -> SDoc
374 pprRules rules = vcat (map pprRule rules)
376 pprRule :: CoreRule -> SDoc
377 pprRule (BuiltinRule { ru_fn = fn, ru_name = name})
378 = ptext (sLit "Built in rule for") <+> ppr fn <> colon <+> doubleQuotes (ftext name)
380 pprRule (Rule { ru_name = name, ru_act = act, ru_fn = fn,
381 ru_bndrs = tpl_vars, ru_args = tpl_args,
383 = hang (doubleQuotes (ftext name) <+> ppr act)
384 4 (sep [ptext (sLit "forall") <+> braces (sep (map pprTypedBinder tpl_vars)),
385 nest 2 (ppr fn <+> sep (map pprArg tpl_args)),
386 nest 2 (ptext (sLit "=") <+> pprCoreExpr rhs)