From 4e608544ebe87dd991d53ded5267f14f5df93b8b Mon Sep 17 00:00:00 2001 From: Adam Chlipala Date: Sun, 10 Oct 2010 20:33:10 -0400 Subject: :::_ notation; switch to TooDeep error message --- doc/manual.tex | 2 +- src/elab_err.sig | 1 + src/elab_err.sml | 2 ++ src/elaborate.sml | 4 ++-- src/urweb.grm | 12 ++++++++++-- src/urweb.lex | 1 + 6 files changed, 17 insertions(+), 5 deletions(-) diff --git a/doc/manual.tex b/doc/manual.tex index 9dbdb505..ebeb2d55 100644 --- a/doc/manual.tex +++ b/doc/manual.tex @@ -495,7 +495,7 @@ A tuple type $(\tau_1, \ldots, \tau_n)$ expands to a record type $\{1 = \tau_1, In general, several adjacent $\lambda$ forms may be combined into one, and kind and type annotations may be omitted, in which case they are implicitly included as wildcards. More formally, for constructor-level abstractions, we can define a new non-terminal $b ::= x \mid (x :: \kappa) \mid X$ and allow composite abstractions of the form $\lambda b^+ \Rightarrow c$, elaborating into the obvious sequence of one core $\lambda$ per element of $b^+$. -In some contexts, the parser isn't happy with token sequences like $x :: \_$, to indicate a constructor variable of wildcard kind. In such cases, write the second two tokens as $::\hspace{-.05in}\_$, with no intervening spaces. +In some contexts, the parser isn't happy with token sequences like $x :: \_$, to indicate a constructor variable of wildcard kind. In such cases, write the second two tokens as $::\hspace{-.05in}\_$, with no intervening spaces. Analogous syntax $:::\hspace{-.05in}\_$ is available for implicit constructor arguments. For any signature item or declaration that defines some entity to be equal to $A$ with classification annotation $B$ (e.g., $\mt{val} \; x : B = A$), $B$ and the preceding colon (or similar punctuation) may be omitted, in which case it is filled in as a wildcard. diff --git a/src/elab_err.sig b/src/elab_err.sig index fbe55a5b..3dfd5d4e 100644 --- a/src/elab_err.sig +++ b/src/elab_err.sig @@ -58,6 +58,7 @@ signature ELAB_ERR = sig | CRecordFailure of Elab.con * Elab.con * (Elab.con * Elab.con * Elab.con) option | TooLifty of ErrorMsg.span * ErrorMsg.span | TooUnify of Elab.con * Elab.con + | TooDeep val cunifyError : ElabEnv.env -> cunify_error -> unit diff --git a/src/elab_err.sml b/src/elab_err.sml index f8a16294..7d5e6be8 100644 --- a/src/elab_err.sml +++ b/src/elab_err.sml @@ -121,6 +121,7 @@ datatype cunify_error = | CRecordFailure of con * con * (con * con * con) option | TooLifty of ErrorMsg.span * ErrorMsg.span | TooUnify of con * con + | TooDeep fun cunifyError env err = case err of @@ -162,6 +163,7 @@ fun cunifyError env err = (ErrorMsg.errorAt (#2 c1) "Substitution in constructor is blocked by a too-deep unification variable"; eprefaces' [("Replacement", p_con env c1), ("Body", p_con env c2)]) + | TooDeep => ErrorMsg.error "Can't reverse-engineer unification variable lifting" datatype exp_error = UnboundExp of ErrorMsg.span * string diff --git a/src/elaborate.sml b/src/elaborate.sml index 7bf687e2..dcae4650 100644 --- a/src/elaborate.sml +++ b/src/elaborate.sml @@ -1079,13 +1079,13 @@ err COccursCheckFailed else (r := SOME (squish nl c2All) - handle CantSquish => err CIncompatible) + handle CantSquish => err (fn _ => TooDeep)) | (_, L'.CUnif (nl, _, _, _, r)) => if occursCon r c1All then err COccursCheckFailed else (r := SOME (squish nl c1All) - handle CantSquish => err CIncompatible) + handle CantSquish => err (fn _ => TooDeep)) | (L'.CUnit, L'.CUnit) => () diff --git a/src/urweb.grm b/src/urweb.grm index 0c85ad7f..21c4a50c 100644 --- a/src/urweb.grm +++ b/src/urweb.grm @@ -212,7 +212,7 @@ fun tnamesOf (e, _) = | STRING of string | INT of Int64.int | FLOAT of Real64.real | CHAR of char | SYMBOL of string | CSYMBOL of string | LPAREN | RPAREN | LBRACK | RBRACK | LBRACE | RBRACE - | EQ | COMMA | COLON | DCOLON | DCOLONWILD | TCOLON | DOT | HASH | UNDER | UNDERUNDER | BAR + | EQ | COMMA | COLON | DCOLON | DCOLONWILD | TCOLON | TCOLONWILD | DOT | HASH | UNDER | UNDERUNDER | BAR | PLUS | MINUS | DIVIDE | DOTDOTDOT | MOD | AT | CON | LTYPE | VAL | REC | AND | FUN | MAP | UNIT | KUNIT | CLASS | DATATYPE | OF @@ -394,7 +394,7 @@ fun tnamesOf (e, _) = %left ANDALSO %left ORELSE %nonassoc COLON -%nonassoc DCOLON TCOLON +%nonassoc DCOLON TCOLON DCOLONWILD TCOLONWILD %left UNION INTERSECT EXCEPT %right COMMA %right JOIN INNER CROSS OUTER LEFT RIGHT FULL @@ -1111,6 +1111,14 @@ earga : LBRACK SYMBOL RBRACK (fn (e, t) => ((ECAbs (kcolon, SYMBOL, kind, e), loc), (TCFun (kcolon, SYMBOL, kind, t), loc)) end) + | LBRACK SYMBOL TCOLONWILD RBRACK (fn (e, t) => + let + val loc = s (LBRACKleft, RBRACKright) + val kind = (KWild, loc) + in + ((ECAbs (Implicit, SYMBOL, kind, e), loc), + (TCFun (Implicit, SYMBOL, kind, t), loc)) + end) | LBRACK cexp TWIDDLE cexp RBRACK(fn (e, t) => let val loc = s (LBRACKleft, RBRACKright) diff --git a/src/urweb.lex b/src/urweb.lex index a6df5f1b..fa8c5dde 100644 --- a/src/urweb.lex +++ b/src/urweb.lex @@ -371,6 +371,7 @@ xint = x[0-9a-fA-F][0-9a-fA-F]; "<=" => (Tokens.LE (pos yypos, pos yypos + size yytext)); ">=" => (Tokens.GE (pos yypos, pos yypos + size yytext)); "," => (Tokens.COMMA (pos yypos, pos yypos + size yytext)); + ":::_" => (Tokens.TCOLONWILD (pos yypos, pos yypos + size yytext)); ":::" => (Tokens.TCOLON (pos yypos, pos yypos + size yytext)); "::_" => (Tokens.DCOLONWILD (pos yypos, pos yypos + size yytext)); "::" => (Tokens.DCOLON (pos yypos, pos yypos + size yytext)); -- cgit v1.2.3