Mercurial > urweb
diff src/urweb.grm @ 2009:799be3911ce3
Monadic bind supports patterns
| author | Adam Chlipala <adam@chlipala.net> |
|---|---|
| date | Fri, 02 May 2014 17:16:02 -0400 |
| parents | 93ff76058825 |
| children | 403f0cc65b9c |
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--- a/src/urweb.grm Fri May 02 15:32:10 2014 -0400 +++ b/src/urweb.grm Fri May 02 17:16:02 2014 -0400 @@ -322,6 +322,39 @@ (EApp (e', ob), loc) end +fun patternOut (e : exp) = + case #1 e of + EWild => (PWild, #2 e) + | EVar ([], x, Infer) => + if Char.isUpper (String.sub (x, 0)) then + (PCon ([], x, NONE), #2 e) + else + (PVar x, #2 e) + | EVar (xs, x, Infer) => + if Char.isUpper (String.sub (x, 0)) then + (PCon (xs, x, NONE), #2 e) + else + (ErrorMsg.errorAt (#2 e) "Badly capitalized constructor name in pattern"; + (PWild, #2 e)) + | EPrim p => (PPrim p, #2 e) + | EApp ((EVar (xs, x, Infer), _), e') => + (PCon (xs, x, SOME (patternOut e')), #2 e) + | ERecord (xes, flex) => + (PRecord (map (fn (x, e') => + let + val x = + case #1 x of + CName x => x + | _ => (ErrorMsg.errorAt (#2 e) "Field name not constant in pattern"; + "") + in + (x, patternOut e') + end) xes, flex), #2 e) + | EAnnot (e', t) => + (PAnnot (patternOut e', t), #2 e) + | _ => (ErrorMsg.errorAt (#2 e) "This is an expression but not a pattern."; + (PWild, #2 e)) + %% %header (functor UrwebLrValsFn(structure Token : TOKEN)) @@ -428,13 +461,13 @@ | eapps of exp | eterm of exp | etuple of exp list - | rexp of (con * exp) list + | rexp of (con * exp) list * bool | xml of exp | xmlOne of exp | xmlOpt of exp | tag of (string * exp) * exp option * exp option * exp | tagHead of string * exp - | bind of string * con option * exp + | bind of pat * con option * exp | edecl of edecl | edecls of edecl list @@ -730,10 +763,10 @@ val e = (EApp (e, mat), loc) val e = (EApp (e, texp), loc) in - (EApp (e, (ERecord [((CName "OnDelete", loc), - findMode Delete), - ((CName "OnUpdate", loc), - findMode Update)], loc)), loc) + (EApp (e, (ERecord ([((CName "OnDelete", loc), + findMode Delete), + ((CName "OnUpdate", loc), + findMode Update)], false), loc)), loc) end) | LBRACE eexp RBRACE (eexp) @@ -779,7 +812,7 @@ val witness = map (fn (c, _) => (c, (EWild, loc))) (#1 tnames :: #2 tnames) - val witness = (ERecord witness, loc) + val witness = (ERecord (witness, false), loc) in (EApp (e, witness), loc) end) @@ -1136,11 +1169,17 @@ end) | bind SEMI eexp (let val loc = s (bindleft, eexpright) - val (v, to, e1) = bind + val (p, to, e1) = bind val e = (EVar (["Basis"], "bind", Infer), loc) val e = (EApp (e, e1), loc) + + val f = case #1 p of + PVar v => (EAbs (v, to, eexp), loc) + | _ => (EAbs ("$x", to, + (ECase ((EVar ([], "$x", Infer), loc), + [(p, eexp)]), loc)), loc) in - (EApp (e, (EAbs (v, to, eexp), loc)), loc) + (EApp (e, f), loc) end) | eexp EQ eexp (native_op ("eq", eexp1, eexp2, s (eexp1left, eexp2right))) | eexp NE eexp (native_op ("ne", eexp1, eexp2, s (eexp1left, eexp2right))) @@ -1181,17 +1220,17 @@ val loc = s (eappsleft, eexpright) in (EApp ((EVar (["Basis"], "Cons", Infer), loc), - (ERecord [((CName "1", loc), - eapps), - ((CName "2", loc), - eexp)], loc)), loc) + (ERecord ([((CName "1", loc), + eapps), + ((CName "2", loc), + eexp)], false), loc)), loc) end) -bind : SYMBOL LARROW eapps (SYMBOL, NONE, eapps) +bind : eapps LARROW eapps (patternOut eapps1, NONE, eapps2) | eapps (let val loc = s (eappsleft, eappsright) in - ("_", SOME (TRecord (CRecord [], loc), loc), eapps) + ((PVar "_", loc), SOME (TRecord (CRecord [], loc), loc), eapps) end) eargs : earg (earg) @@ -1289,7 +1328,7 @@ in (ERecord (ListUtil.mapi (fn (i, e) => ((CName (Int.toString (i + 1)), loc), - e)) etuple), loc) + e)) etuple, false), loc) end) | path (EVar (#1 path, #2 path, Infer), s (pathleft, pathright)) @@ -1299,7 +1338,8 @@ | AT cpath (EVar (#1 cpath, #2 cpath, TypesOnly), s (ATleft, cpathright)) | AT AT cpath (EVar (#1 cpath, #2 cpath, DontInfer), s (AT1left, cpathright)) | LBRACE rexp RBRACE (ERecord rexp, s (LBRACEleft, RBRACEright)) - | UNIT (ERecord [], s (UNITleft, UNITright)) + | LBRACE RBRACE (ERecord ([], false), s (LBRACEleft, RBRACEright)) + | UNIT (ERecord ([], false), s (UNITleft, UNITright)) | INT (EPrim (Prim.Int INT), s (INTleft, INTright)) | FLOAT (EPrim (Prim.Float FLOAT), s (FLOATleft, FLOATright)) @@ -1386,7 +1426,7 @@ ^ " vs. " ^ Int.toString (length sqlexps) ^ ")") else (); - (EApp (e, (ERecord (ListPair.zip (fields, sqlexps)), loc)), loc) + (EApp (e, (ERecord (ListPair.zip (fields, sqlexps), false), loc)), loc) end) | LPAREN enterDml UPDATE texp SET fsets CWHERE sqlexp leaveDml RPAREN (let @@ -1394,7 +1434,7 @@ val e = (EVar (["Basis"], "update", Infer), loc) val e = (ECApp (e, (CWild (KRecord (KType, loc), loc), loc)), loc) - val e = (EApp (e, (ERecord fsets, loc)), loc) + val e = (EApp (e, (ERecord (fsets, false), loc)), loc) val e = (EApp (e, texp), loc) in (EApp (e, sqlexp), loc) @@ -1486,9 +1526,9 @@ ptuple : pat COMMA pat ([pat1, pat2]) | pat COMMA ptuple (pat :: ptuple) -rexp : ([]) - | ident EQ eexp ([(ident, eexp)]) - | ident EQ eexp COMMA rexp ((ident, eexp) :: rexp) +rexp : DOTDOTDOT ([], true) + | ident EQ eexp ([(ident, eexp)], false) + | ident EQ eexp COMMA rexp ((ident, eexp) :: #1 rexp, #2 rexp) xml : xmlOne xml (let val pos = s (xmlOneleft, xmlright) @@ -1626,9 +1666,9 @@ ((CName "Data", pos), datas') :: #6 attrs end - val e = (EApp (e, (ERecord atts, pos)), pos) + val e = (EApp (e, (ERecord (atts, false), pos)), pos) val e = (EApp (e, (EApp (#2 tagHead, - (ERecord [], pos)), pos)), pos) + (ERecord ([], false), pos)), pos)), pos) in (tagHead, #1 attrs, #2 attrs, e) end) @@ -1708,14 +1748,14 @@ query : query1 obopt lopt ofopt (let val loc = s (query1left, query1right) - val re = (ERecord [((CName "Rows", loc), - query1), - ((CName "OrderBy", loc), - obopt), - ((CName "Limit", loc), - lopt), - ((CName "Offset", loc), - ofopt)], loc) + val re = (ERecord ([((CName "Rows", loc), + query1), + ((CName "OrderBy", loc), + obopt), + ((CName "Limit", loc), + lopt), + ((CName "Offset", loc), + ofopt)], false), loc) in (EApp ((EVar (["Basis"], "sql_query", Infer), loc), re), loc) end) @@ -1796,21 +1836,21 @@ val e = (EVar (["Basis"], "sql_query1", Infer), loc) val e = (ECApp (e, (CRecord (map (fn nm => (nm, (CUnit, loc))) empties), loc)), loc) - val re = (ERecord [((CName "Distinct", loc), - dopt), - ((CName "From", loc), - #2 tables), - ((CName "Where", loc), - wopt), - ((CName "GroupBy", loc), - grp), - ((CName "Having", loc), - hopt), - ((CName "SelectFields", loc), - (ECApp ((EVar (["Basis"], "sql_subset", Infer), loc), - sel), loc)), - ((CName "SelectExps", loc), - (ERecord exps, loc))], loc) + val re = (ERecord ([((CName "Distinct", loc), + dopt), + ((CName "From", loc), + #2 tables), + ((CName "Where", loc), + wopt), + ((CName "GroupBy", loc), + grp), + ((CName "Having", loc), + hopt), + ((CName "SelectFields", loc), + (ECApp ((EVar (["Basis"], "sql_subset", Infer), loc), + sel), loc)), + ((CName "SelectExps", loc), + (ERecord (exps, false), loc))], false), loc) val e = (EApp (e, re), loc) in