/* perly.y
*
- * Copyright (c) 1991-1994, Larry Wall
+ * Copyright (c) 1991-2002, 2003, 2004 Larry Wall
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
/*
* 'I see,' laughed Strider. 'I look foul and feel fair. Is that it?
- * All that is gold does not glitter, not all those that wander are lost.'
+ * All that is gold does not glitter, not all those who wander are lost.'
*/
-%{
-#include "EXTERN.h"
-#include "perl.h"
+/* This file holds the grammar for the Perl language. If edited, you need
+ * to run regen_perly.pl, which re-creates the files perly.h, perly.tab
+ * and perly.act which are derived from this.
+ *
+ * The main job of of this grammar is to call the various newFOO()
+ * functions in op.c to build a syntax tree of OP structs.
+ * It relies on the lexer in toke.c to do the tokenizing.
+ */
-static void
-dep()
-{
- deprecate("\"do\" to call subroutines");
-}
+/* Make the parser re-entrant. */
-%}
+%pure_parser
%start prog
GV *gvval;
}
-%token <ival> '{' ')'
+%token <ival> '{'
%token <opval> WORD METHOD FUNCMETH THING PMFUNC PRIVATEREF
%token <opval> FUNC0SUB UNIOPSUB LSTOPSUB
%token <ival> FORMAT SUB ANONSUB PACKAGE USE
%token <ival> WHILE UNTIL IF UNLESS ELSE ELSIF CONTINUE FOR
%token <ival> LOOPEX DOTDOT
-%token <ival> FUNC0 FUNC1 FUNC
+%token <ival> FUNC0 FUNC1 FUNC UNIOP LSTOP
%token <ival> RELOP EQOP MULOP ADDOP
%token <ival> DOLSHARP DO HASHBRACK NOAMP
-%token LOCAL MY
+%token <ival> LOCAL MY MYSUB
+%token COLONATTR
-%type <ival> prog decl local format startsub remember mremember '&'
+%type <ival> prog decl format startsub startanonsub startformsub
+%type <ival> progstart remember mremember '&' savescope
%type <opval> block mblock lineseq line loop cond else
-%type <opval> expr term scalar ary hsh arylen star amper sideff
+%type <opval> expr term subscripted scalar ary hsh arylen star amper sideff
%type <opval> argexpr nexpr texpr iexpr mexpr mnexpr mtexpr miexpr
-%type <opval> listexpr listexprcom indirob
-%type <opval> listop method proto cont my_scalar
+%type <opval> listexpr listexprcom indirob listop method
+%type <opval> formname subname proto subbody cont my_scalar
+%type <opval> subattrlist myattrlist mysubrout myattrterm myterm
+%type <opval> termbinop termunop anonymous termdo
%type <pval> label
-%left <ival> OROP
+%nonassoc PREC_LOW
+%nonassoc LOOPEX
+
+%left <ival> OROP DOROP
%left ANDOP
%right NOTOP
-%nonassoc <ival> LSTOP
+%nonassoc LSTOP LSTOPSUB
%left ','
%right <ival> ASSIGNOP
%right '?' ':'
%nonassoc DOTDOT
-%left OROR
+%left OROR DORDOR
%left ANDAND
%left <ival> BITOROP
%left <ival> BITANDOP
%nonassoc EQOP
%nonassoc RELOP
-%nonassoc <ival> UNIOP
+%nonassoc UNIOP UNIOPSUB
%left <ival> SHIFTOP
%left ADDOP
%left MULOP
%right <ival> POWOP
%nonassoc PREINC PREDEC POSTINC POSTDEC
%left ARROW
+%nonassoc <ival> ')'
%left '('
+%left '[' '{'
%% /* RULES */
-prog : /* NULL */
- {
-#if defined(YYDEBUG) && defined(DEBUGGING)
- yydebug = (debug & 1);
-#endif
- expect = XSTATE;
- }
+/* The whole program */
+prog : progstart
/*CONTINUED*/ lineseq
- { newPROG($2); }
+ { $$ = $1; newPROG(block_end($1,$2)); }
;
+/* An ordinary block */
block : '{' remember lineseq '}'
- { $$ = block_end($1,$2,$3); }
+ { if (PL_copline > (line_t)$1)
+ PL_copline = (line_t)$1;
+ $$ = block_end($2, $3); }
;
remember: /* NULL */ /* start a full lexical scope */
{ $$ = block_start(TRUE); }
;
+progstart:
+ {
+ PL_expect = XSTATE; $$ = block_start(TRUE);
+ }
+ ;
+
+
mblock : '{' mremember lineseq '}'
- { $$ = block_end($1,$2,$3); }
+ { if (PL_copline > (line_t)$1)
+ PL_copline = (line_t)$1;
+ $$ = block_end($2, $3); }
;
mremember: /* NULL */ /* start a partial lexical scope */
{ $$ = block_start(FALSE); }
;
+savescope: /* NULL */ /* remember stack pos in case of error */
+ { $$ = PL_savestack_ix; }
+
+/* A collection of "lines" in the program */
lineseq : /* NULL */
{ $$ = Nullop; }
| lineseq decl
{ $$ = $1; }
- | lineseq line
- { $$ = append_list(OP_LINESEQ,
- (LISTOP*)$1, (LISTOP*)$2);
- pad_reset_pending = TRUE;
- if ($1 && $2) hints |= HINT_BLOCK_SCOPE; }
+ | lineseq savescope line
+ { LEAVE_SCOPE($2);
+ $$ = append_list(OP_LINESEQ,
+ (LISTOP*)$1, (LISTOP*)$3);
+ PL_pad_reset_pending = TRUE;
+ if ($1 && $3) PL_hints |= HINT_BLOCK_SCOPE; }
;
+/* A "line" in the program */
line : label cond
{ $$ = newSTATEOP(0, $1, $2); }
| loop /* loops add their own labels */
}
else {
$$ = Nullop;
- copline = NOLINE;
+ PL_copline = NOLINE;
}
- expect = XSTATE; }
+ PL_expect = XSTATE; }
| label sideff ';'
{ $$ = newSTATEOP(0, $1, $2);
- expect = XSTATE; }
+ PL_expect = XSTATE; }
;
+/* An expression which may have a side-effect */
sideff : error
{ $$ = Nullop; }
| expr
{ $$ = newLOOPOP(OPf_PARENS, 1, scalar($3), $1); }
| expr UNTIL iexpr
{ $$ = newLOOPOP(OPf_PARENS, 1, $3, $1);}
+ | expr FOR expr
+ { $$ = newFOROP(0, Nullch, (line_t)$2,
+ Nullop, $3, $1, Nullop); }
;
+/* else and elsif blocks */
else : /* NULL */
{ $$ = Nullop; }
| ELSE mblock
- { $$ = scope($2); }
+ { ($2)->op_flags |= OPf_PARENS; $$ = scope($2); }
| ELSIF '(' mexpr ')' mblock else
- { copline = $1;
- $$ = newSTATEOP(0, Nullch,
- newCONDOP(0, $3, scope($5), $6));
- hints |= HINT_BLOCK_SCOPE; }
+ { PL_copline = (line_t)$1;
+ $$ = newCONDOP(0, $3, scope($5), $6);
+ PL_hints |= HINT_BLOCK_SCOPE; }
;
+/* Real conditional expressions */
cond : IF '(' remember mexpr ')' mblock else
- { copline = $1;
- $$ = block_end($1, $3,
+ { PL_copline = (line_t)$1;
+ $$ = block_end($3,
newCONDOP(0, $4, scope($6), $7)); }
| UNLESS '(' remember miexpr ')' mblock else
- { copline = $1;
- $$ = block_end($1, $3,
+ { PL_copline = (line_t)$1;
+ $$ = block_end($3,
newCONDOP(0, $4, scope($6), $7)); }
- | IF block block else
- { copline = $1;
- deprecate("if BLOCK BLOCK");
- $$ = newCONDOP(0, scope($2), scope($3), $4); }
- | UNLESS block block else
- { copline = $1;
- deprecate("unless BLOCK BLOCK");
- $$ = newCONDOP(0, invert(scalar(scope($2))),
- scope($3), $4); }
;
+/* Continue blocks */
cont : /* NULL */
{ $$ = Nullop; }
| CONTINUE block
{ $$ = scope($2); }
;
+/* Loops: while, until, for, and a bare block */
loop : label WHILE '(' remember mtexpr ')' mblock cont
- { copline = $2;
- $$ = block_end($2, $4,
+ { PL_copline = (line_t)$2;
+ $$ = block_end($4,
newSTATEOP(0, $1,
newWHILEOP(0, 1, (LOOP*)Nullop,
- $5, $7, $8))); }
+ $2, $5, $7, $8))); }
| label UNTIL '(' remember miexpr ')' mblock cont
- { copline = $2;
- $$ = block_end($2, $4,
+ { PL_copline = (line_t)$2;
+ $$ = block_end($4,
newSTATEOP(0, $1,
newWHILEOP(0, 1, (LOOP*)Nullop,
- $5, $7, $8))); }
- | label WHILE block block cont
- { copline = $2;
- $$ = newWHILEOP(0, 1, (LOOP*)Nullop,
- scope($3), $4, $5); }
- | label UNTIL block block cont
- { copline = $2;
- $$ = newWHILEOP(0, 1, (LOOP*)Nullop,
- invert(scalar(scope($3))),
- $4, $5); }
+ $2, $5, $7, $8))); }
| label FOR MY remember my_scalar '(' mexpr ')' mblock cont
- { $$ = block_end($2, $4,
- newFOROP(0, $1, $2, $5, $7, $9, $10)); }
+ { $$ = block_end($4,
+ newFOROP(0, $1, (line_t)$2, $5, $7, $9, $10)); }
| label FOR scalar '(' remember mexpr ')' mblock cont
- { $$ = block_end($2, $5,
- newFOROP(0, $1, $2, mod($3, OP_ENTERLOOP),
+ { $$ = block_end($5,
+ newFOROP(0, $1, (line_t)$2, mod($3, OP_ENTERLOOP),
$6, $8, $9)); }
| label FOR '(' remember mexpr ')' mblock cont
- { $$ = block_end($2, $4,
- newFOROP(0, $1, $2, Nullop, $5, $7, $8)); }
+ { $$ = block_end($4,
+ newFOROP(0, $1, (line_t)$2, Nullop, $5, $7, $8)); }
| label FOR '(' remember mnexpr ';' mtexpr ';' mnexpr ')' mblock
/* basically fake up an initialize-while lineseq */
- { copline = $2;
- $$ = block_end($2, $4,
- append_elem(OP_LINESEQ, scalar($5),
- newSTATEOP(0, $1,
- newWHILEOP(0, 1, (LOOP*)Nullop,
- scalar($7),
- $11, scalar($9))))); }
+ { OP *forop;
+ PL_copline = (line_t)$2;
+ forop = newSTATEOP(0, $1,
+ newWHILEOP(0, 1, (LOOP*)Nullop,
+ $2, scalar($7),
+ $11, $9));
+ if ($5) {
+ forop = append_elem(OP_LINESEQ,
+ newSTATEOP(0, ($1?savepv($1):Nullch),
+ $5),
+ forop);
+ }
+
+ $$ = block_end($4, forop); }
| label block cont /* a block is a loop that happens once */
- { $$ = newSTATEOP(0,
- $1, newWHILEOP(0, 1, (LOOP*)Nullop,
- Nullop, $2, $3)); }
+ { $$ = newSTATEOP(0, $1,
+ newWHILEOP(0, 1, (LOOP*)Nullop,
+ NOLINE, Nullop, $2, $3)); }
;
+/* Normal expression */
nexpr : /* NULL */
{ $$ = Nullop; }
| sideff
;
+/* Boolean expression */
texpr : /* NULL means true */
- { (void)scan_num("1"); $$ = yylval.opval; }
+ { (void)scan_num("1", &yylval); $$ = yylval.opval; }
| expr
;
+/* Inverted boolean expression */
iexpr : expr
{ $$ = invert(scalar($1)); }
;
+/* Expression with its own lexical scope */
mexpr : expr
{ $$ = $1; intro_my(); }
;
{ $$ = $1; intro_my(); }
;
+/* Optional "MAIN:"-style loop labels */
label : /* empty */
{ $$ = Nullch; }
| LABEL
;
+/* Some kind of declaration - does not take part in the parse tree */
decl : format
{ $$ = 0; }
| subrout
{ $$ = 0; }
+ | mysubrout
+ { $$ = 0; }
| package
{ $$ = 0; }
| use
{ $$ = 0; }
;
-format : FORMAT startsub WORD block
+format : FORMAT startformsub formname block
{ newFORM($2, $3, $4); }
- | FORMAT startsub block
- { newFORM($2, Nullop, $3); }
;
-subrout : SUB startsub WORD proto block
- { newSUB($2, $3, $4, $5); }
- | SUB startsub WORD proto ';'
- { newSUB($2, $3, $4, Nullop); expect = XSTATE; }
+formname: WORD { $$ = $1; }
+ | /* NULL */ { $$ = Nullop; }
+ ;
+
+/* Unimplemented "my sub foo { }" */
+mysubrout: MYSUB startsub subname proto subattrlist subbody
+ { newMYSUB($2, $3, $4, $5, $6); }
+ ;
+
+/* Subroutine definition */
+subrout : SUB startsub subname proto subattrlist subbody
+ { newATTRSUB($2, $3, $4, $5, $6); }
+ ;
+
+startsub: /* NULL */ /* start a regular subroutine scope */
+ { $$ = start_subparse(FALSE, 0); }
;
+startanonsub: /* NULL */ /* start an anonymous subroutine scope */
+ { $$ = start_subparse(FALSE, CVf_ANON); }
+ ;
+
+startformsub: /* NULL */ /* start a format subroutine scope */
+ { $$ = start_subparse(TRUE, 0); }
+ ;
+
+/* Name of a subroutine - must be a bareword, could be special */
+subname : WORD { STRLEN n_a; char *name = SvPV(((SVOP*)$1)->op_sv,n_a);
+ if (strEQ(name, "BEGIN") || strEQ(name, "END")
+ || strEQ(name, "INIT") || strEQ(name, "CHECK"))
+ CvSPECIAL_on(PL_compcv);
+ $$ = $1; }
+ ;
+
+/* Subroutine prototype */
proto : /* NULL */
{ $$ = Nullop; }
| THING
;
-
-startsub: /* NULL */ /* start a subroutine scope */
- { $$ = start_subparse(); }
+
+/* Optional list of subroutine attributes */
+subattrlist: /* NULL */
+ { $$ = Nullop; }
+ | COLONATTR THING
+ { $$ = $2; }
+ | COLONATTR
+ { $$ = Nullop; }
+ ;
+
+/* List of attributes for a "my" variable declaration */
+myattrlist: COLONATTR THING
+ { $$ = $2; }
+ | COLONATTR
+ { $$ = Nullop; }
+ ;
+
+/* Subroutine body - either null or a block */
+subbody : block { $$ = $1; }
+ | ';' { $$ = Nullop; PL_expect = XSTATE; }
;
package : PACKAGE WORD ';'
{ package($2); }
- | PACKAGE ';'
- { package(Nullop); }
;
-use : USE startsub WORD WORD listexpr ';'
- { utilize($1, $2, $3, $4, $5); }
+use : USE startsub
+ { CvSPECIAL_on(PL_compcv); /* It's a BEGIN {} */ }
+ WORD WORD listexpr ';'
+ { utilize($1, $2, $4, $5, $6); }
;
+/* Ordinary expressions; logical combinations */
expr : expr ANDOP expr
{ $$ = newLOGOP(OP_AND, 0, $1, $3); }
| expr OROP expr
{ $$ = newLOGOP($2, 0, $1, $3); }
- | argexpr
+ | expr DOROP expr
+ { $$ = newLOGOP(OP_DOR, 0, $1, $3); }
+ | argexpr %prec PREC_LOW
;
+/* Expressions are a list of terms joined by commas */
argexpr : argexpr ','
{ $$ = $1; }
| argexpr ',' term
{ $$ = append_elem(OP_LIST, $1, $3); }
- | term
+ | term %prec PREC_LOW
;
-listop : LSTOP indirob argexpr
+/* List operators */
+listop : LSTOP indirob argexpr /* print $fh @args */
{ $$ = convert($1, OPf_STACKED,
prepend_elem(OP_LIST, newGVREF($1,$2), $3) ); }
- | FUNC '(' indirob expr ')'
+ | FUNC '(' indirob expr ')' /* print ($fh @args */
{ $$ = convert($1, OPf_STACKED,
prepend_elem(OP_LIST, newGVREF($1,$3), $4) ); }
- | term ARROW method '(' listexprcom ')'
+ | term ARROW method '(' listexprcom ')' /* $foo->bar(list) */
{ $$ = convert(OP_ENTERSUB, OPf_STACKED,
append_elem(OP_LIST,
prepend_elem(OP_LIST, scalar($1), $5),
newUNOP(OP_METHOD, 0, $3))); }
- | METHOD indirob listexpr
+ | term ARROW method /* $foo->bar */
+ { $$ = convert(OP_ENTERSUB, OPf_STACKED,
+ append_elem(OP_LIST, scalar($1),
+ newUNOP(OP_METHOD, 0, $3))); }
+ | METHOD indirob listexpr /* new Class @args */
{ $$ = convert(OP_ENTERSUB, OPf_STACKED,
append_elem(OP_LIST,
prepend_elem(OP_LIST, $2, $3),
newUNOP(OP_METHOD, 0, $1))); }
- | FUNCMETH indirob '(' listexprcom ')'
+ | FUNCMETH indirob '(' listexprcom ')' /* method $object (@args) */
{ $$ = convert(OP_ENTERSUB, OPf_STACKED,
append_elem(OP_LIST,
prepend_elem(OP_LIST, $2, $4),
newUNOP(OP_METHOD, 0, $1))); }
- | LSTOP listexpr
+ | LSTOP listexpr /* print @args */
{ $$ = convert($1, 0, $2); }
- | FUNC '(' listexprcom ')'
+ | FUNC '(' listexprcom ')' /* print (@args) */
{ $$ = convert($1, 0, $3); }
- | LSTOPSUB startsub block listexpr %prec LSTOP
+ | LSTOPSUB startanonsub block /* map { foo } ... */
+ { $3 = newANONATTRSUB($2, 0, Nullop, $3); }
+ listexpr %prec LSTOP /* ... @bar */
{ $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
- append_elem(OP_LIST,
- prepend_elem(OP_LIST, newANONSUB($2, 0, $3), $4),
- $1)); }
+ append_elem(OP_LIST,
+ prepend_elem(OP_LIST, $3, $5), $1)); }
;
+/* Names of methods. May use $object->$methodname */
method : METHOD
| scalar
;
-term : term ASSIGNOP term
+/* Some kind of subscripted expression */
+subscripted: star '{' expr ';' '}' /* *main::{something} */
+ /* In this and all the hash accessors, ';' is
+ * provided by the tokeniser */
+ { $$ = newBINOP(OP_GELEM, 0, $1, scalar($3));
+ PL_expect = XOPERATOR; }
+ | scalar '[' expr ']' /* $array[$element] */
+ { $$ = newBINOP(OP_AELEM, 0, oopsAV($1), scalar($3)); }
+ | term ARROW '[' expr ']' /* somearef->[$element] */
+ { $$ = newBINOP(OP_AELEM, 0,
+ ref(newAVREF($1),OP_RV2AV),
+ scalar($4));}
+ | subscripted '[' expr ']' /* $foo->[$bar]->[$baz] */
+ { $$ = newBINOP(OP_AELEM, 0,
+ ref(newAVREF($1),OP_RV2AV),
+ scalar($3));}
+ | scalar '{' expr ';' '}' /* $foo->{bar();} */
+ { $$ = newBINOP(OP_HELEM, 0, oopsHV($1), jmaybe($3));
+ PL_expect = XOPERATOR; }
+ | term ARROW '{' expr ';' '}' /* somehref->{bar();} */
+ { $$ = newBINOP(OP_HELEM, 0,
+ ref(newHVREF($1),OP_RV2HV),
+ jmaybe($4));
+ PL_expect = XOPERATOR; }
+ | subscripted '{' expr ';' '}' /* $foo->[bar]->{baz;} */
+ { $$ = newBINOP(OP_HELEM, 0,
+ ref(newHVREF($1),OP_RV2HV),
+ jmaybe($3));
+ PL_expect = XOPERATOR; }
+ | term ARROW '(' ')' /* $subref->() */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
+ newCVREF(0, scalar($1))); }
+ | term ARROW '(' expr ')' /* $subref->(@args) */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
+ append_elem(OP_LIST, $4,
+ newCVREF(0, scalar($1)))); }
+
+ | subscripted '(' expr ')' /* $foo->{bar}->(@args) */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
+ append_elem(OP_LIST, $3,
+ newCVREF(0, scalar($1)))); }
+ | subscripted '(' ')' /* $foo->{bar}->() */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
+ newCVREF(0, scalar($1))); }
+ ;
+
+/* Binary operators between terms */
+termbinop : term ASSIGNOP term /* $x = $y */
{ $$ = newASSIGNOP(OPf_STACKED, $1, $2, $3); }
- | term POWOP term
+ | term POWOP term /* $x ** $y */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term MULOP term
+ | term MULOP term /* $x * $y, $x x $y */
{ if ($2 != OP_REPEAT)
scalar($1);
$$ = newBINOP($2, 0, $1, scalar($3)); }
- | term ADDOP term
+ | term ADDOP term /* $x + $y */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term SHIFTOP term
+ | term SHIFTOP term /* $x >> $y, $x << $y */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term RELOP term
+ | term RELOP term /* $x > $y, etc. */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term EQOP term
+ | term EQOP term /* $x == $y, $x eq $y */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term BITANDOP term
+ | term BITANDOP term /* $x & $y */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term BITOROP term
+ | term BITOROP term /* $x | $y */
{ $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
- | term DOTDOT term
+ | term DOTDOT term /* $x..$y, $x...$y */
{ $$ = newRANGE($2, scalar($1), scalar($3));}
- | term ANDAND term
+ | term ANDAND term /* $x && $y */
{ $$ = newLOGOP(OP_AND, 0, $1, $3); }
- | term OROR term
+ | term OROR term /* $x || $y */
{ $$ = newLOGOP(OP_OR, 0, $1, $3); }
- | term '?' term ':' term
- { $$ = newCONDOP(0, $1, $3, $5); }
- | term MATCHOP term
+ | term DORDOR term /* $x // $y */
+ { $$ = newLOGOP(OP_DOR, 0, $1, $3); }
+ | term MATCHOP term /* $x =~ /$y/ */
{ $$ = bind_match($2, $1, $3); }
+ ;
- | '-' term %prec UMINUS
+/* Unary operators and terms */
+termunop : '-' term %prec UMINUS /* -$x */
{ $$ = newUNOP(OP_NEGATE, 0, scalar($2)); }
- | '+' term %prec UMINUS
+ | '+' term %prec UMINUS /* +$x */
{ $$ = $2; }
- | '!' term
+ | '!' term /* !$x */
{ $$ = newUNOP(OP_NOT, 0, scalar($2)); }
- | '~' term
+ | '~' term /* ~$x */
{ $$ = newUNOP(OP_COMPLEMENT, 0, scalar($2));}
- | REFGEN term
- { $$ = newUNOP(OP_REFGEN, 0, mod($2,OP_REFGEN)); }
- | term POSTINC
+ | term POSTINC /* $x++ */
{ $$ = newUNOP(OP_POSTINC, 0,
mod(scalar($1), OP_POSTINC)); }
- | term POSTDEC
+ | term POSTDEC /* $x-- */
{ $$ = newUNOP(OP_POSTDEC, 0,
mod(scalar($1), OP_POSTDEC)); }
- | PREINC term
+ | PREINC term /* ++$x */
{ $$ = newUNOP(OP_PREINC, 0,
mod(scalar($2), OP_PREINC)); }
- | PREDEC term
+ | PREDEC term /* --$x */
{ $$ = newUNOP(OP_PREDEC, 0,
mod(scalar($2), OP_PREDEC)); }
- | local term %prec UNIOP
+
+ ;
+
+/* Constructors for anonymous data */
+anonymous: '[' expr ']'
+ { $$ = newANONLIST($2); }
+ | '[' ']'
+ { $$ = newANONLIST(Nullop); }
+ | HASHBRACK expr ';' '}' %prec '(' /* { foo => "Bar" } */
+ { $$ = newANONHASH($2); }
+ | HASHBRACK ';' '}' %prec '(' /* { } (';' by tokener) */
+ { $$ = newANONHASH(Nullop); }
+ | ANONSUB startanonsub proto subattrlist block %prec '('
+ { $$ = newANONATTRSUB($2, $3, $4, $5); }
+
+ ;
+
+/* Things called with "do" */
+termdo : DO term %prec UNIOP /* do $filename */
+ { $$ = dofile($2); }
+ | DO block %prec '(' /* do { code */
+ { $$ = newUNOP(OP_NULL, OPf_SPECIAL, scope($2)); }
+ | DO WORD '(' ')' /* do somesub() */
+ { $$ = newUNOP(OP_ENTERSUB,
+ OPf_SPECIAL|OPf_STACKED,
+ prepend_elem(OP_LIST,
+ scalar(newCVREF(
+ (OPpENTERSUB_AMPER<<8),
+ scalar($2)
+ )),Nullop)); dep();}
+ | DO WORD '(' expr ')' /* do somesub(@args) */
+ { $$ = newUNOP(OP_ENTERSUB,
+ OPf_SPECIAL|OPf_STACKED,
+ append_elem(OP_LIST,
+ $4,
+ scalar(newCVREF(
+ (OPpENTERSUB_AMPER<<8),
+ scalar($2)
+ )))); dep();}
+ | DO scalar '(' ')' /* do $subref () */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_SPECIAL|OPf_STACKED,
+ prepend_elem(OP_LIST,
+ scalar(newCVREF(0,scalar($2))), Nullop)); dep();}
+ | DO scalar '(' expr ')' /* do $subref (@args) */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_SPECIAL|OPf_STACKED,
+ prepend_elem(OP_LIST,
+ $4,
+ scalar(newCVREF(0,scalar($2))))); dep();}
+
+ ;
+
+term : termbinop
+ | termunop
+ | anonymous
+ | termdo
+ | term '?' term ':' term
+ { $$ = newCONDOP(0, $1, $3, $5); }
+ | REFGEN term /* \$x, \@y, \%z */
+ { $$ = newUNOP(OP_REFGEN, 0, mod($2,OP_REFGEN)); }
+ | myattrterm %prec UNIOP
+ { $$ = $1; }
+ | LOCAL term %prec UNIOP
{ $$ = localize($2,$1); }
| '(' expr ')'
{ $$ = sawparens($2); }
| '(' ')'
{ $$ = sawparens(newNULLLIST()); }
- | '[' expr ']' %prec '('
- { $$ = newANONLIST($2); }
- | '[' ']' %prec '('
- { $$ = newANONLIST(Nullop); }
- | HASHBRACK expr ';' '}' %prec '('
- { $$ = newANONHASH($2); }
- | HASHBRACK ';' '}' %prec '('
- { $$ = newANONHASH(Nullop); }
- | ANONSUB startsub proto block %prec '('
- { $$ = newANONSUB($2, $3, $4); }
| scalar %prec '('
{ $$ = $1; }
- | star '{' expr ';' '}'
- { $$ = newBINOP(OP_GELEM, 0, newGVREF(0,$1), $3); }
| star %prec '('
{ $$ = $1; }
- | scalar '[' expr ']' %prec '('
- { $$ = newBINOP(OP_AELEM, 0, oopsAV($1), scalar($3)); }
- | term ARROW '[' expr ']' %prec '('
- { $$ = newBINOP(OP_AELEM, 0,
- ref(newAVREF($1),OP_RV2AV),
- scalar($4));}
- | term '[' expr ']' %prec '('
- { assertref($1); $$ = newBINOP(OP_AELEM, 0,
- ref(newAVREF($1),OP_RV2AV),
- scalar($3));}
| hsh %prec '('
{ $$ = $1; }
| ary %prec '('
{ $$ = $1; }
- | arylen %prec '('
+ | arylen %prec '(' /* $#x, $#{ something } */
{ $$ = newUNOP(OP_AV2ARYLEN, 0, ref($1, OP_AV2ARYLEN));}
- | scalar '{' expr ';' '}' %prec '('
- { $$ = newBINOP(OP_HELEM, 0, oopsHV($1), jmaybe($3));
- expect = XOPERATOR; }
- | term ARROW '{' expr ';' '}' %prec '('
- { $$ = newBINOP(OP_HELEM, 0,
- ref(newHVREF($1),OP_RV2HV),
- jmaybe($4));
- expect = XOPERATOR; }
- | term '{' expr ';' '}' %prec '('
- { assertref($1); $$ = newBINOP(OP_HELEM, 0,
- ref(newHVREF($1),OP_RV2HV),
- jmaybe($3));
- expect = XOPERATOR; }
- | '(' expr ')' '[' expr ']' %prec '('
+ | subscripted
+ { $$ = $1; }
+ | '(' expr ')' '[' expr ']' /* list slice */
{ $$ = newSLICEOP(0, $5, $2); }
- | '(' ')' '[' expr ']' %prec '('
+ | '(' ')' '[' expr ']' /* empty list slice! */
{ $$ = newSLICEOP(0, $4, Nullop); }
- | ary '[' expr ']' %prec '('
+ | ary '[' expr ']' /* array slice */
{ $$ = prepend_elem(OP_ASLICE,
newOP(OP_PUSHMARK, 0),
newLISTOP(OP_ASLICE, 0,
list($3),
ref($1, OP_ASLICE))); }
- | ary '{' expr ';' '}' %prec '('
+ | ary '{' expr ';' '}' /* @hash{@keys} */
{ $$ = prepend_elem(OP_HSLICE,
newOP(OP_PUSHMARK, 0),
newLISTOP(OP_HSLICE, 0,
list($3),
ref(oopsHV($1), OP_HSLICE)));
- expect = XOPERATOR; }
+ PL_expect = XOPERATOR; }
| THING %prec '('
{ $$ = $1; }
- | amper
+ | amper /* &foo; */
{ $$ = newUNOP(OP_ENTERSUB, 0, scalar($1)); }
- | amper '(' ')'
+ | amper '(' ')' /* &foo() */
{ $$ = newUNOP(OP_ENTERSUB, OPf_STACKED, scalar($1)); }
- | amper '(' expr ')'
+ | amper '(' expr ')' /* &foo(@args) */
{ $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
append_elem(OP_LIST, $3, scalar($1))); }
- | NOAMP WORD listexpr
+ | NOAMP WORD listexpr /* foo(@args) */
{ $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
append_elem(OP_LIST, $3, scalar($2))); }
- | DO term %prec UNIOP
- { $$ = newUNOP(OP_DOFILE, 0, scalar($2)); }
- | DO block %prec '('
- { $$ = newUNOP(OP_NULL, OPf_SPECIAL, scope($2)); }
- | DO WORD '(' ')'
- { $$ = newUNOP(OP_ENTERSUB,
- OPf_SPECIAL|OPf_STACKED,
- prepend_elem(OP_LIST,
- scalar(newCVREF(
- (OPpENTERSUB_AMPER<<8),
- scalar($2)
- )),Nullop)); dep();}
- | DO WORD '(' expr ')'
- { $$ = newUNOP(OP_ENTERSUB,
- OPf_SPECIAL|OPf_STACKED,
- append_elem(OP_LIST,
- $4,
- scalar(newCVREF(
- (OPpENTERSUB_AMPER<<8),
- scalar($2)
- )))); dep();}
- | DO scalar '(' ')'
- { $$ = newUNOP(OP_ENTERSUB, OPf_SPECIAL|OPf_STACKED,
- prepend_elem(OP_LIST,
- scalar(newCVREF(0,scalar($2))), Nullop)); dep();}
- | DO scalar '(' expr ')'
- { $$ = newUNOP(OP_ENTERSUB, OPf_SPECIAL|OPf_STACKED,
- prepend_elem(OP_LIST,
- $4,
- scalar(newCVREF(0,scalar($2))))); dep();}
- | LOOPEX
+ | LOOPEX /* loop exiting command (goto, last, dump, etc) */
{ $$ = newOP($1, OPf_SPECIAL);
- hints |= HINT_BLOCK_SCOPE; }
+ PL_hints |= HINT_BLOCK_SCOPE; }
| LOOPEX term
{ $$ = newLOOPEX($1,$2); }
- | NOTOP argexpr
+ | NOTOP argexpr /* not $foo */
{ $$ = newUNOP(OP_NOT, 0, scalar($2)); }
- | UNIOP
+ | UNIOP /* Unary op, $_ implied */
{ $$ = newOP($1, 0); }
- | UNIOP block
+ | UNIOP block /* eval { foo } */
{ $$ = newUNOP($1, 0, $2); }
- | UNIOP term
+ | UNIOP term /* Unary op */
{ $$ = newUNOP($1, 0, $2); }
- | UNIOPSUB term
+ | UNIOPSUB term /* Sub treated as unop */
{ $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
append_elem(OP_LIST, $2, scalar($1))); }
- | FUNC0
+ | FUNC0 /* Nullary operator */
{ $$ = newOP($1, 0); }
| FUNC0 '(' ')'
{ $$ = newOP($1, 0); }
- | FUNC0SUB
- { $$ = newUNOP(OP_ENTERSUB, 0,
+ | FUNC0SUB /* Sub treated as nullop */
+ { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
scalar($1)); }
- | FUNC1 '(' ')'
+ | FUNC1 '(' ')' /* not () */
{ $$ = newOP($1, OPf_SPECIAL); }
- | FUNC1 '(' expr ')'
+ | FUNC1 '(' expr ')' /* not($foo) */
{ $$ = newUNOP($1, 0, $3); }
- | PMFUNC '(' term ')'
+ | PMFUNC '(' term ')' /* /foo/ */
{ $$ = pmruntime($1, $3, Nullop); }
- | PMFUNC '(' term ',' term ')'
+ | PMFUNC '(' term ',' term ')' /* s/foo/bar/ (or tr) */
{ $$ = pmruntime($1, $3, $5); }
| WORD
| listop
;
-listexpr: /* NULL */
+/* "my" declarations, with optional attributes */
+myattrterm: MY myterm myattrlist
+ { $$ = my_attrs($2,$3); }
+ | MY myterm
+ { $$ = localize($2,$1); }
+ ;
+
+/* Things that can be "my"'d */
+myterm : '(' expr ')'
+ { $$ = sawparens($2); }
+ | '(' ')'
+ { $$ = sawparens(newNULLLIST()); }
+ | scalar %prec '('
+ { $$ = $1; }
+ | hsh %prec '('
+ { $$ = $1; }
+ | ary %prec '('
+ { $$ = $1; }
+ ;
+
+/* Basic list expressions */
+listexpr: /* NULL */ %prec PREC_LOW
{ $$ = Nullop; }
- | argexpr
+ | argexpr %prec PREC_LOW
{ $$ = $1; }
;
{ $$ = $1; }
;
-local : LOCAL { $$ = 0; }
- | MY { $$ = 1; }
- ;
-
+/* A little bit of trickery to make "for my $foo (@bar)" actually be
+ lexical */
my_scalar: scalar
- { in_my = 0; $$ = my($1); }
+ { PL_in_my = 0; $$ = my($1); }
;
amper : '&' indirob
{ $$ = newGVREF(0,$2); }
;
+/* Indirect objects */
indirob : WORD
{ $$ = scalar($1); }
- | scalar
+ | scalar %prec PREC_LOW
{ $$ = scalar($1); }
| block
{ $$ = scope($1); }
| PRIVATEREF
{ $$ = $1; }
;
-
-%% /* PROGRAM */
https://perl5.git.perl.org / perl5.git / blobdiff