} while (( o = traverse_op_tree(top, o)) != NULL);
}
-/*
-=for apidoc op_lvalue
-
-Propagate lvalue ("modifiable") context to an op and its children.
-C<type> represents the context type, roughly based on the type of op that
-would do the modifying, although C<local()> is represented by C<OP_NULL>,
-because it has no op type of its own (it is signalled by a flag on
-the lvalue op).
-
-This function detects things that can't be modified, such as C<$x+1>, and
-generates errors for them. For example, C<$x+1 = 2> would cause it to be
-called with an op of type C<OP_ADD> and a C<type> argument of C<OP_SASSIGN>.
-
-It also flags things that need to behave specially in an lvalue context,
-such as C<$$x = 5> which might have to vivify a reference in C<$x>.
-
-=cut
-*/
-
static void
S_mark_padname_lvalue(pTHX_ PADNAME *pn)
{
return 0;
}
+
+/* apply lvalue reference (aliasing) context to the optree o.
+ * E.g. in
+ * \($x,$y) = (...)
+ * o would be the list ($x,$y) and type would be OP_AASSIGN.
+ * It may descend and apply this to children too, for example in
+ * \( $cond ? $x, $y) = (...)
+ */
+
static void
S_lvref(pTHX_ OP *o, I32 type)
{
dVAR;
OP *kid;
- switch (o->op_type) {
- case OP_COND_EXPR:
- for (kid = OpSIBLING(cUNOPo->op_first); kid;
- kid = OpSIBLING(kid))
- S_lvref(aTHX_ kid, type);
- /* FALLTHROUGH */
- case OP_PUSHMARK:
- return;
- case OP_RV2AV:
- if (cUNOPo->op_first->op_type != OP_GV) goto badref;
- o->op_flags |= OPf_STACKED;
- if (o->op_flags & OPf_PARENS) {
- if (o->op_private & OPpLVAL_INTRO) {
- yyerror(Perl_form(aTHX_ "Can't modify reference to "
- "localized parenthesized array in list assignment"));
- return;
- }
- slurpy:
- OpTYPE_set(o, OP_LVAVREF);
- o->op_private &= OPpLVAL_INTRO|OPpPAD_STATE;
- o->op_flags |= OPf_MOD|OPf_REF;
- return;
- }
- o->op_private |= OPpLVREF_AV;
- goto checkgv;
- case OP_RV2CV:
- kid = cUNOPo->op_first;
- if (kid->op_type == OP_NULL)
- kid = cUNOPx(OpSIBLING(kUNOP->op_first))
- ->op_first;
- o->op_private = OPpLVREF_CV;
- if (kid->op_type == OP_GV)
- o->op_flags |= OPf_STACKED;
- else if (kid->op_type == OP_PADCV) {
- o->op_targ = kid->op_targ;
- kid->op_targ = 0;
- op_free(cUNOPo->op_first);
- cUNOPo->op_first = NULL;
- o->op_flags &=~ OPf_KIDS;
- }
- else goto badref;
- break;
- case OP_RV2HV:
- if (o->op_flags & OPf_PARENS) {
- parenhash:
- yyerror(Perl_form(aTHX_ "Can't modify reference to "
- "parenthesized hash in list assignment"));
- return;
- }
- o->op_private |= OPpLVREF_HV;
- /* FALLTHROUGH */
- case OP_RV2SV:
- checkgv:
- if (cUNOPo->op_first->op_type != OP_GV) goto badref;
- o->op_flags |= OPf_STACKED;
- break;
- case OP_PADHV:
- if (o->op_flags & OPf_PARENS) goto parenhash;
- o->op_private |= OPpLVREF_HV;
- /* FALLTHROUGH */
- case OP_PADSV:
- PAD_COMPNAME_GEN_set(o->op_targ, PERL_INT_MAX);
- break;
- case OP_PADAV:
- PAD_COMPNAME_GEN_set(o->op_targ, PERL_INT_MAX);
- if (o->op_flags & OPf_PARENS) goto slurpy;
- o->op_private |= OPpLVREF_AV;
- break;
- case OP_AELEM:
- case OP_HELEM:
- o->op_private |= OPpLVREF_ELEM;
- o->op_flags |= OPf_STACKED;
- break;
- case OP_ASLICE:
- case OP_HSLICE:
- OpTYPE_set(o, OP_LVREFSLICE);
- o->op_private &= OPpLVAL_INTRO;
- return;
- case OP_NULL:
- if (o->op_flags & OPf_SPECIAL) /* do BLOCK */
- goto badref;
- else if (!(o->op_flags & OPf_KIDS))
- return;
- if (o->op_targ != OP_LIST) {
- S_lvref(aTHX_ cBINOPo->op_first, type);
- return;
- }
- /* FALLTHROUGH */
- case OP_LIST:
- for (kid = cLISTOPo->op_first; kid; kid = OpSIBLING(kid)) {
- assert((kid->op_flags & OPf_WANT) != OPf_WANT_VOID);
- S_lvref(aTHX_ kid, type);
- }
- return;
- case OP_STUB:
- if (o->op_flags & OPf_PARENS)
- return;
- /* FALLTHROUGH */
- default:
- badref:
- /* diag_listed_as: Can't modify reference to %s in %s assignment */
- yyerror(Perl_form(aTHX_ "Can't modify reference to %s in %s",
- o->op_type == OP_NULL && o->op_flags & OPf_SPECIAL
- ? "do block"
- : OP_DESC(o),
- PL_op_desc[type]));
- return;
- }
- OpTYPE_set(o, OP_LVREF);
- o->op_private &=
- OPpLVAL_INTRO|OPpLVREF_ELEM|OPpLVREF_TYPE|OPpPAD_STATE;
- if (type == OP_ENTERLOOP)
- o->op_private |= OPpLVREF_ITER;
+ OP * top_op = o;
+
+ while (1) {
+ switch (o->op_type) {
+ case OP_COND_EXPR:
+ o = OpSIBLING(cUNOPo->op_first);
+ continue;
+
+ case OP_PUSHMARK:
+ goto do_next;
+
+ case OP_RV2AV:
+ if (cUNOPo->op_first->op_type != OP_GV) goto badref;
+ o->op_flags |= OPf_STACKED;
+ if (o->op_flags & OPf_PARENS) {
+ if (o->op_private & OPpLVAL_INTRO) {
+ yyerror(Perl_form(aTHX_ "Can't modify reference to "
+ "localized parenthesized array in list assignment"));
+ goto do_next;
+ }
+ slurpy:
+ OpTYPE_set(o, OP_LVAVREF);
+ o->op_private &= OPpLVAL_INTRO|OPpPAD_STATE;
+ o->op_flags |= OPf_MOD|OPf_REF;
+ goto do_next;
+ }
+ o->op_private |= OPpLVREF_AV;
+ goto checkgv;
+
+ case OP_RV2CV:
+ kid = cUNOPo->op_first;
+ if (kid->op_type == OP_NULL)
+ kid = cUNOPx(OpSIBLING(kUNOP->op_first))
+ ->op_first;
+ o->op_private = OPpLVREF_CV;
+ if (kid->op_type == OP_GV)
+ o->op_flags |= OPf_STACKED;
+ else if (kid->op_type == OP_PADCV) {
+ o->op_targ = kid->op_targ;
+ kid->op_targ = 0;
+ op_free(cUNOPo->op_first);
+ cUNOPo->op_first = NULL;
+ o->op_flags &=~ OPf_KIDS;
+ }
+ else goto badref;
+ break;
+
+ case OP_RV2HV:
+ if (o->op_flags & OPf_PARENS) {
+ parenhash:
+ yyerror(Perl_form(aTHX_ "Can't modify reference to "
+ "parenthesized hash in list assignment"));
+ goto do_next;
+ }
+ o->op_private |= OPpLVREF_HV;
+ /* FALLTHROUGH */
+ case OP_RV2SV:
+ checkgv:
+ if (cUNOPo->op_first->op_type != OP_GV) goto badref;
+ o->op_flags |= OPf_STACKED;
+ break;
+
+ case OP_PADHV:
+ if (o->op_flags & OPf_PARENS) goto parenhash;
+ o->op_private |= OPpLVREF_HV;
+ /* FALLTHROUGH */
+ case OP_PADSV:
+ PAD_COMPNAME_GEN_set(o->op_targ, PERL_INT_MAX);
+ break;
+
+ case OP_PADAV:
+ PAD_COMPNAME_GEN_set(o->op_targ, PERL_INT_MAX);
+ if (o->op_flags & OPf_PARENS) goto slurpy;
+ o->op_private |= OPpLVREF_AV;
+ break;
+
+ case OP_AELEM:
+ case OP_HELEM:
+ o->op_private |= OPpLVREF_ELEM;
+ o->op_flags |= OPf_STACKED;
+ break;
+
+ case OP_ASLICE:
+ case OP_HSLICE:
+ OpTYPE_set(o, OP_LVREFSLICE);
+ o->op_private &= OPpLVAL_INTRO;
+ goto do_next;
+
+ case OP_NULL:
+ if (o->op_flags & OPf_SPECIAL) /* do BLOCK */
+ goto badref;
+ else if (!(o->op_flags & OPf_KIDS))
+ goto do_next;
+
+ /* the code formerly only recursed into the first child of
+ * a non ex-list OP_NULL. if we ever encounter such a null op with
+ * more than one child, need to decide whether its ok to process
+ * *all* its kids or not */
+ assert(o->op_targ == OP_LIST
+ || !(OpHAS_SIBLING(cBINOPo->op_first)));
+ /* FALLTHROUGH */
+ case OP_LIST:
+ o = cLISTOPo->op_first;
+ continue;
+
+ case OP_STUB:
+ if (o->op_flags & OPf_PARENS)
+ goto do_next;
+ /* FALLTHROUGH */
+ default:
+ badref:
+ /* diag_listed_as: Can't modify reference to %s in %s assignment */
+ yyerror(Perl_form(aTHX_ "Can't modify reference to %s in %s",
+ o->op_type == OP_NULL && o->op_flags & OPf_SPECIAL
+ ? "do block"
+ : OP_DESC(o),
+ PL_op_desc[type]));
+ goto do_next;
+ }
+
+ OpTYPE_set(o, OP_LVREF);
+ o->op_private &=
+ OPpLVAL_INTRO|OPpLVREF_ELEM|OPpLVREF_TYPE|OPpPAD_STATE;
+ if (type == OP_ENTERLOOP)
+ o->op_private |= OPpLVREF_ITER;
+
+ do_next:
+ while (1) {
+ if (o == top_op)
+ return; /* at top; no parents/siblings to try */
+ if (OpHAS_SIBLING(o)) {
+ o = o->op_sibparent;
+ break;
+ }
+ o = o->op_sibparent; /*try parent's next sibling */
+ }
+ } /* while */
}
+
PERL_STATIC_INLINE bool
S_potential_mod_type(I32 type)
{
|| type == OP_REFGEN || type == OP_LEAVESUBLV;
}
+
+/*
+=for apidoc op_lvalue
+
+Propagate lvalue ("modifiable") context to an op and its children.
+C<type> represents the context type, roughly based on the type of op that
+would do the modifying, although C<local()> is represented by C<OP_NULL>,
+because it has no op type of its own (it is signalled by a flag on
+the lvalue op).
+
+This function detects things that can't be modified, such as C<$x+1>, and
+generates errors for them. For example, C<$x+1 = 2> would cause it to be
+called with an op of type C<OP_ADD> and a C<type> argument of C<OP_SASSIGN>.
+
+It also flags things that need to behave specially in an lvalue context,
+such as C<$$x = 5> which might have to vivify a reference in C<$x>.
+
+=cut
+
+Perl_op_lvalue_flags() is a non-API lower-level interface to
+op_lvalue(). The flags param has these bits:
+ OP_LVALUE_NO_CROAK: return rather than croaking on error
+
+*/
+
OP *
Perl_op_lvalue_flags(pTHX_ OP *o, I32 type, U32 flags)
{
return o;
}
- assert( (o->op_flags & OPf_WANT) != OPf_WANT_VOID );
+ /* elements of a list might be in void context because the list is
+ in scalar context or because they are attribute sub calls */
+ if ((o->op_flags & OPf_WANT) == OPf_WANT_VOID)
+ return o;
if (type == OP_PRTF || type == OP_SPRINTF) type = OP_ENTERSUB;
case OP_LIST:
localize = 0;
for (kid = cLISTOPo->op_first; kid; kid = OpSIBLING(kid))
- /* elements might be in void context because the list is
- in scalar context or because they are attribute sub calls */
- if ( (kid->op_flags & OPf_WANT) != OPf_WANT_VOID )
- op_lvalue(kid, type);
+ op_lvalue(kid, type);
break;
case OP_COREARGS:
return o;
}
-/* Does this look like a boolean operation? For these purposes
+
+/* For the purposes of 'when(implied_smartmatch)'
+ * versus 'when(boolean_expression)',
+ * does this look like a boolean operation? For these purposes
a boolean operation is:
- a subroutine call [*]
- a logical connective
}
}
+
/*
=for apidoc newGIVENOP
https://perl5.git.perl.org / perl5.git / blobdiff