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Update URLs to be https://
[perl5.git] / perly.y
diff --git a/perly.y b/perly.y
index 0a7c30c..0325d66 100644 (file)
--- a/perly.y
+++ b/perly.y
     GV *gvval;
 }
 
-%token <ival> GRAMPROG GRAMEXPR GRAMBLOCK GRAMBARESTMT GRAMFULLSTMT GRAMSTMTSEQ
+%token <ival> GRAMPROG GRAMEXPR GRAMBLOCK GRAMBARESTMT GRAMFULLSTMT GRAMSTMTSEQ GRAMSUBSIGNATURE
 
 %token <ival> '{' '}' '[' ']' '-' '+' '@' '%' '&' '=' '.'
 
 %token <opval> BAREWORD METHOD FUNCMETH THING PMFUNC PRIVATEREF QWLIST
 %token <opval> FUNC0OP FUNC0SUB UNIOPSUB LSTOPSUB
 %token <opval> PLUGEXPR PLUGSTMT
-%token <pval> LABEL
-%token <ival> FORMAT SUB ANONSUB PACKAGE USE
+%token <opval> LABEL
+%token <ival> FORMAT SUB SIGSUB ANONSUB ANON_SIGSUB PACKAGE USE
 %token <ival> WHILE UNTIL IF UNLESS ELSE ELSIF CONTINUE FOR
 %token <ival> GIVEN WHEN DEFAULT
 %token <ival> LOOPEX DOTDOT YADAYADA
@@ -60,6 +60,7 @@
 %token <ival> DOLSHARP DO HASHBRACK NOAMP
 %token <ival> LOCAL MY REQUIRE
 %token <ival> COLONATTR FORMLBRACK FORMRBRACK
+%token <ival> SUBLEXSTART SUBLEXEND
 
 %type <ival> grammar remember mremember
 %type <ival>  startsub startanonsub startformsub
 %type <opval> sliceme kvslice gelem
 %type <opval> listexpr nexpr texpr iexpr mexpr mnexpr
 %type <opval> optlistexpr optexpr optrepl indirob listop method
-%type <opval> formname subname proto optsubbody cont my_scalar my_var
+%type <opval> formname subname proto cont my_scalar my_var
 %type <opval> refgen_topic formblock
 %type <opval> subattrlist myattrlist myattrterm myterm
 %type <opval> termbinop termunop anonymous termdo
 %type <ival>  sigslurpsigil
 %type <opval> sigvarname sigdefault sigscalarelem sigslurpelem
-%type <opval> sigelem siglist siglistornull subsignature 
+%type <opval> sigelem siglist siglistornull subsigguts subsignature optsubsignature
+%type <opval> subbody optsubbody sigsubbody optsigsubbody
 %type <opval> formstmtseq formline formarg
 
 %nonassoc <ival> PREC_LOW
@@ -184,6 +186,16 @@ grammar    :       GRAMPROG
                          PL_eval_root = $3;
                          $$ = 0;
                        }
+       |       GRAMSUBSIGNATURE
+                       {
+                         parser->expect = XSTATE;
+                         $<ival>$ = 0;
+                       }
+               subsigguts
+                       {
+                         PL_eval_root = $3;
+                         $$ = 0;
+                       }
        ;
 
 /* An ordinary block */
@@ -252,11 +264,17 @@ fullstmt: barestmt
 
 labfullstmt:   LABEL barestmt
                        {
-                         $$ = newSTATEOP(SVf_UTF8 * $1[strlen($1)+1], $1, $2);
+                          SV *label = cSVOPx_sv($1);
+                         $$ = newSTATEOP(SvFLAGS(label) & SVf_UTF8,
+                                            savepv(SvPVX_const(label)), $2);
+                          op_free($1);
                        }
        |       LABEL labfullstmt
                        {
-                         $$ = newSTATEOP(SVf_UTF8 * $1[strlen($1)+1], $1, $2);
+                          SV *label = cSVOPx_sv($1);
+                         $$ = newSTATEOP(SvFLAGS(label) & SVf_UTF8,
+                                            savepv(SvPVX_const(label)), $2);
+                          op_free($1);
                        }
        ;
 
@@ -274,28 +292,14 @@ barestmt: PLUGSTMT
                          parser->parsed_sub = 1;
                        }
        |       SUB subname startsub
+                    /* sub declaration or definition not within scope
+                       of 'use feature "signatures"'*/
                        {
-                         if ($2->op_type == OP_CONST) {
-                           const char *const name =
-                               SvPV_nolen_const(((SVOP*)$2)->op_sv);
-                           if (strEQ(name, "BEGIN") || strEQ(name, "END")
-                             || strEQ(name, "INIT") || strEQ(name, "CHECK")
-                             || strEQ(name, "UNITCHECK"))
-                             CvSPECIAL_on(PL_compcv);
-                         }
-                         else
-                         /* State subs inside anonymous subs need to be
-                            clonable themselves. */
-                         if (CvANON(CvOUTSIDE(PL_compcv))
-                          || CvCLONE(CvOUTSIDE(PL_compcv))
-                          || !PadnameIsSTATE(PadlistNAMESARRAY(CvPADLIST(
-                                               CvOUTSIDE(PL_compcv)
-                                            ))[$2->op_targ]))
-                             CvCLONE_on(PL_compcv);
+                          init_named_cv(PL_compcv, $2);
                          parser->in_my = 0;
                          parser->in_my_stash = NULL;
                        }
-               proto subattrlist optsubbody
+                    proto subattrlist optsubbody
                        {
                          SvREFCNT_inc_simple_void(PL_compcv);
                          $2->op_type == OP_CONST
@@ -306,40 +310,22 @@ barestmt: PLUGSTMT
                          intro_my();
                          parser->parsed_sub = 1;
                        }
-       |       SUB subname startsub
+       |       SIGSUB subname startsub
+                    /* sub declaration or definition under 'use feature
+                     * "signatures"'. (Note that a signature isn't
+                     * allowed in a declaration)
+                     */
                        {
-                         if ($2->op_type == OP_CONST) {
-                           const char *const name =
-                               SvPV_nolen_const(((SVOP*)$2)->op_sv);
-                           if (strEQ(name, "BEGIN") || strEQ(name, "END")
-                             || strEQ(name, "INIT") || strEQ(name, "CHECK")
-                             || strEQ(name, "UNITCHECK"))
-                             CvSPECIAL_on(PL_compcv);
-                         }
-                         else
-                         /* State subs inside anonymous subs need to be
-                            clonable themselves. */
-                         if (CvANON(CvOUTSIDE(PL_compcv))
-                          || CvCLONE(CvOUTSIDE(PL_compcv))
-                          || !PadnameIsSTATE(PadlistNAMESARRAY(CvPADLIST(
-                                               CvOUTSIDE(PL_compcv)
-                                            ))[$2->op_targ]))
-                             CvCLONE_on(PL_compcv);
+                          init_named_cv(PL_compcv, $2);
                          parser->in_my = 0;
                          parser->in_my_stash = NULL;
                        }
-               remember subsignature subattrlist '{' stmtseq '}'
+                    subattrlist optsigsubbody
                        {
-                         OP *body;
-                         if (parser->copline > (line_t)$8)
-                             parser->copline = (line_t)$8;
-                         body = block_end($5,
-                               op_append_list(OP_LINESEQ, $6, $9));
-
                          SvREFCNT_inc_simple_void(PL_compcv);
                          $2->op_type == OP_CONST
-                             ? newATTRSUB($3, $2, NULL, $7, body)
-                             : newMYSUB($3, $2, NULL, $7, body)
+                             ? newATTRSUB($3, $2, NULL, $5, $6)
+                             : newMYSUB(  $3, $2, NULL, $5, $6)
                          ;
                          $$ = NULL;
                          intro_my();
@@ -780,8 +766,17 @@ siglistornull:             /* NULL */
        |       siglist
                        { $$ = $1; }
 
+/* optional subroutine signature */
+optsubsignature:       /* NULL */
+                       { $$ = NULL; }
+       |       subsignature
+                       { $$ = $1; }
+
 /* Subroutine signature */
-subsignature:  '('
+subsignature:  '(' subsigguts ')'
+                       { $$ = $2; }
+
+subsigguts:
                         {
                             ENTER;
                             SAVEIV(parser->sig_elems);
@@ -793,50 +788,94 @@ subsignature:     '('
                             parser->in_my        = KEY_sigvar;
                         }
                 siglistornull
-                ')'
                        {
-                            OP            *sigops = $3;
-                            UNOP_AUX_item *aux;
+                            OP            *sigops = $2;
+                            struct op_argcheck_aux *aux;
                             OP            *check;
 
-                            if (!parser->error_count) {
-                                assert(FEATURE_SIGNATURES_IS_ENABLED);
-                            }
+                           if (!FEATURE_SIGNATURES_IS_ENABLED)
+                               Perl_croak(aTHX_ "Experimental "
+                                    "subroutine signatures not enabled");
 
                             /* We shouldn't get here otherwise */
                             Perl_ck_warner_d(aTHX_
                                 packWARN(WARN_EXPERIMENTAL__SIGNATURES),
                                 "The signatures feature is experimental");
 
-                            aux = (UNOP_AUX_item*)PerlMemShared_malloc(
-                                sizeof(UNOP_AUX_item) * 3);
-                            aux[0].iv = parser->sig_elems;
-                            aux[1].iv = parser->sig_optelems;
-                            aux[2].iv = parser->sig_slurpy;
-                            check = newUNOP_AUX(OP_ARGCHECK, 0, NULL, aux);
+                            aux = (struct op_argcheck_aux*)
+                                    PerlMemShared_malloc(
+                                        sizeof(struct op_argcheck_aux));
+                            aux->params     = parser->sig_elems;
+                            aux->opt_params = parser->sig_optelems;
+                            aux->slurpy     = parser->sig_slurpy;
+                            check = newUNOP_AUX(OP_ARGCHECK, 0, NULL,
+                                            (UNOP_AUX_item *)aux);
                             sigops = op_prepend_elem(OP_LINESEQ, check, sigops);
                             sigops = op_prepend_elem(OP_LINESEQ,
                                                 newSTATEOP(0, NULL, NULL),
                                                 sigops);
                             /* a nextstate at the end handles context
                              * correctly for an empty sub body */
-                            $$ = op_append_elem(OP_LINESEQ,
+                            sigops = op_append_elem(OP_LINESEQ,
                                                 sigops,
                                                 newSTATEOP(0, NULL, NULL));
+                            /* wrap the list of arg ops in a NULL aux op.
+                              This serves two purposes. First, it makes
+                              the arg list a separate subtree from the
+                              body of the sub, and secondly the null op
+                              may in future be upgraded to an OP_SIGNATURE
+                              when implemented. For now leave it as
+                              ex-argcheck */
+                            $$ = newUNOP_AUX(OP_ARGCHECK, 0, sigops, NULL);
+                            op_null($$);
 
                             parser->in_my = 0;
+                            /* tell the toker that attrributes can follow
+                             * this sig, but only so that the toker
+                             * can skip through any (illegal) trailing
+                             * attribute text then give a useful error
+                             * message about "attributes before sig",
+                             * rather than falling over ina mess at
+                             * unrecognised syntax.
+                             */
                             parser->expect = XATTRBLOCK;
+                            parser->sig_seen = TRUE;
                             LEAVE;
                        }
        ;
 
+/* Optional subroutine body (for named subroutine declaration) */
+optsubbody:    subbody { $$ = $1; }
+       |       ';'     { $$ = NULL; }
+       ;
 
 
-/* Optional subroutine body, for named subroutine declaration */
-optsubbody:    block
-       |       ';'     { $$ = NULL; }
+/* Subroutine body (without signature) */
+subbody:       remember  '{' stmtseq '}'
+                       {
+                         if (parser->copline > (line_t)$2)
+                             parser->copline = (line_t)$2;
+                         $$ = block_end($1, $3);
+                       }
        ;
 
+
+/* optional [ Subroutine body with optional signature ] (for named
+ * subroutine declaration) */
+optsigsubbody: sigsubbody { $$ = $1; }
+       |       ';'        { $$ = NULL; }
+
+/* Subroutine body with optional signature */
+sigsubbody:    remember optsubsignature '{' stmtseq '}'
+                       {
+                         if (parser->copline > (line_t)$3)
+                             parser->copline = (line_t)$3;
+                         $$ = block_end($1,
+                               op_append_list(OP_LINESEQ, $2, $4));
+                       }
+       ;
+
+
 /* Ordinary expressions; logical combinations */
 expr   :       expr ANDOP expr
                        { $$ = newLOGOP(OP_AND, 0, $1, $3); }
@@ -894,6 +933,8 @@ listop      :       LSTOP indirob listexpr /* map {...} @args or print $fh @args */
                        { $$ = op_convert_list($1, 0, $2); }
        |       FUNC '(' optexpr ')'                 /* print (@args) */
                        { $$ = op_convert_list($1, 0, $3); }
+       |       FUNC SUBLEXSTART optexpr SUBLEXEND          /* uc($arg) from "\U..." */
+                       { $$ = op_convert_list($1, 0, $3); }
        |       LSTOPSUB startanonsub block /* sub f(&@);   f { foo } ... */
                        { SvREFCNT_inc_simple_void(PL_compcv);
                          $<opval>$ = newANONATTRSUB($2, 0, NULL, $3); }
@@ -940,19 +981,31 @@ subscripted:    gelem '{' expr ';' '}'        /* *main::{something} */
                                        jmaybe($3)); }
        |       term ARROW '(' ')'          /* $subref->() */
                        { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
-                                  newCVREF(0, scalar($1))); }
+                                  newCVREF(0, scalar($1)));
+                         if (parser->expect == XBLOCK)
+                             parser->expect = XOPERATOR;
+                       }
        |       term ARROW '(' expr ')'     /* $subref->(@args) */
                        { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
                                   op_append_elem(OP_LIST, $4,
-                                      newCVREF(0, scalar($1)))); }
+                                      newCVREF(0, scalar($1))));
+                         if (parser->expect == XBLOCK)
+                             parser->expect = XOPERATOR;
+                       }
 
        |       subscripted '(' expr ')'   /* $foo->{bar}->(@args) */
                        { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
                                   op_append_elem(OP_LIST, $3,
-                                              newCVREF(0, scalar($1)))); }
+                                              newCVREF(0, scalar($1))));
+                         if (parser->expect == XBLOCK)
+                             parser->expect = XOPERATOR;
+                       }
        |       subscripted '(' ')'        /* $foo->{bar}->() */
                        { $$ = newUNOP(OP_ENTERSUB, OPf_STACKED,
-                                  newCVREF(0, scalar($1))); }
+                                  newCVREF(0, scalar($1)));
+                         if (parser->expect == XBLOCK)
+                             parser->expect = XOPERATOR;
+                       }
        |       '(' expr ')' '[' expr ']'            /* list slice */
                        { $$ = newSLICEOP(0, $5, $2); }
        |       QWLIST '[' expr ']'            /* list literal slice */
@@ -962,7 +1015,7 @@ subscripted:    gelem '{' expr ';' '}'        /* *main::{something} */
     ;
 
 /* Binary operators between terms */
-termbinop:     term ASSIGNOP term                     /* $x = $y */
+termbinop:     term ASSIGNOP term                     /* $x = $y, $x += $y */
                        { $$ = newASSIGNOP(OPf_STACKED, $1, $2, $3); }
        |       term POWOP term                        /* $x ** $y */
                        { $$ = newBINOP($2, 0, scalar($1), scalar($3)); }
@@ -1040,20 +1093,12 @@ anonymous:      '[' expr ']'
                        { $$ = newANONHASH($2); }
        |       HASHBRACK ';' '}'       %prec '(' /* { } (';' by tokener) */
                        { $$ = newANONHASH(NULL); }
-       |       ANONSUB startanonsub proto subattrlist block            %prec '('
+       |       ANONSUB     startanonsub proto subattrlist subbody    %prec '('
                        { SvREFCNT_inc_simple_void(PL_compcv);
                          $$ = newANONATTRSUB($2, $3, $4, $5); }
-       |       ANONSUB startanonsub remember subsignature subattrlist '{' stmtseq '}'  %prec '('
-                       {
-                         OP *body;
-                         if (parser->copline > (line_t)$6)
-                             parser->copline = (line_t)$6;
-                         body = block_end($3,
-                               op_append_list(OP_LINESEQ, $4, $7));
-                         SvREFCNT_inc_simple_void(PL_compcv);
-                         $$ = newANONATTRSUB($2, NULL, $5, body);
-                       }
-
+       |       ANON_SIGSUB startanonsub subattrlist sigsubbody %prec '('
+                       { SvREFCNT_inc_simple_void(PL_compcv);
+                         $$ = newANONATTRSUB($2, NULL, $3, $4); }
     ;
 
 /* Things called with "do" */
@@ -1211,7 +1256,7 @@ term      :       termbinop
                            } else
                                $<ival>$ = 0;
                        }
-                   '(' listexpr optrepl ')'
+                   SUBLEXSTART listexpr optrepl SUBLEXEND
                        { $$ = pmruntime($1, $4, $5, 1, $<ival>2); }
        |       BAREWORD
        |       listop