Amelioration of the error message "Unrecognized character %s in column %d"

[perl5.git] / pp.c

diff --git a/pp.c b/pp.c
index bdbe010..9cedc3f 100644 (file)
--- a/pp.c
+++ b/pp.c
@@ -3912,7 +3912,17 @@ PP(pp_aslice)
 
     if (SvTYPE(av) == SVt_PVAV) {
        const I32 arybase = CopARYBASE_get(PL_curcop);
-       if (lval && PL_op->op_private & OPpLVAL_INTRO) {
+       const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
+       bool can_preserve = FALSE;
+
+       if (localizing) {
+           MAGIC *mg;
+           HV *stash;
+
+           can_preserve = SvCANEXISTDELETE(av);
+       }
+
+       if (lval && localizing) {
            register SV **svp;
            I32 max = -1;
            for (svp = MARK + 1; svp <= SP; svp++) {
@@ -3923,18 +3933,32 @@ PP(pp_aslice)
            if (max > AvMAX(av))
                av_extend(av, max);
        }
+
        while (++MARK <= SP) {
            register SV **svp;
            I32 elem = SvIV(*MARK);
+           bool preeminent = TRUE;
 
            if (elem > 0)
                elem -= arybase;
+           if (localizing && can_preserve) {
+               /* If we can determine whether the element exist,
+                * Try to preserve the existenceness of a tied array
+                * element by using EXISTS and DELETE if possible.
+                * Fallback to FETCH and STORE otherwise. */
+               preeminent = av_exists(av, elem);
+           }
+
            svp = av_fetch(av, elem, lval);
            if (lval) {
                if (!svp || *svp == &PL_sv_undef)
                    DIE(aTHX_ PL_no_aelem, elem);
-               if (PL_op->op_private & OPpLVAL_INTRO)
-                   save_aelem(av, elem, svp);
+               if (localizing) {
+                   if (preeminent)
+                       save_aelem(av, elem, svp);
+                   else
+                       SAVEADELETE(av, elem);
+               }
            }
            *MARK = svp ? *svp : &PL_sv_undef;
        }
@@ -5038,9 +5062,9 @@ PP(pp_lock)
     dSP;
     dTOPss;
     SV *retsv = sv;
+    assert(SvTYPE(retsv) != SVt_PVCV);
     SvLOCK(sv);
-    if (SvTYPE(retsv) == SVt_PVAV || SvTYPE(retsv) == SVt_PVHV
-       || SvTYPE(retsv) == SVt_PVCV) {
+    if (SvTYPE(retsv) == SVt_PVAV || SvTYPE(retsv) == SVt_PVHV) {
        retsv = refto(retsv);
     }
     SETs(retsv);