POD cleanup and rewrapping.

[p5sagit/p5-mst-13.2.git] / pp_hot.c

diff --git a/pp_hot.c b/pp_hot.c
index f2387b4..de2dec4 100644 (file)
--- a/pp_hot.c
+++ b/pp_hot.c
@@ -1643,13 +1643,25 @@ PP(pp_helem)
     I32 preeminent = 0;
 
     if (SvTYPE(hv) == SVt_PVHV) {
-       if (PL_op->op_private & OPpLVAL_INTRO)
+       if (PL_op->op_private & OPpLVAL_INTRO) {
+           MAGIC *mg;
+           HV *stash;
+           /* does the element we're localizing already exist? */
            preeminent =  
-               ( SvRMAGICAL(hv)
-                 && !mg_find((SV*)hv, PERL_MAGIC_tied)
-                 && !mg_find((SV*)hv, PERL_MAGIC_env)
-               ) ? 1 : hv_exists_ent(hv, keysv, 0);
+               /* can we determine whether it exists? */
+               (    !SvRMAGICAL(hv)
+                 || mg_find((SV*)hv, PERL_MAGIC_env)
+                 || (     (mg = mg_find((SV*)hv, PERL_MAGIC_tied))
+                       /* Try to preserve the existenceness of a tied hash
+                        * element by using EXISTS and DELETE if possible.
+                        * Fallback to FETCH and STORE otherwise */
+                       && (stash = SvSTASH(SvRV(SvTIED_obj((SV*)hv, mg))))
+                       && gv_fetchmethod_autoload(stash, "EXISTS", TRUE)
+                       && gv_fetchmethod_autoload(stash, "DELETE", TRUE)
+                   )
+               ) ? hv_exists_ent(hv, keysv, 0) : 1;
 
+       }
        he = hv_fetch_ent(hv, keysv, lval && !defer, hash);
        svp = he ? &HeVAL(he) : 0;
     }
@@ -1687,17 +1699,8 @@ PP(pp_helem)
                    STRLEN keylen;
                    char *key = SvPV(keysv, keylen);
                    SAVEDELETE(hv, savepvn(key,keylen), keylen);
-               } else {
-                   SV *sv;
+               } else
                    save_helem(hv, keysv, svp);
-                   sv = *svp;
-                   /* If we're localizing a tied hash element, this new
-                    * sv won't actually be stored in the hash - so it
-                    * won't get reaped when the localize ends. Ensure it
-                    * gets reaped by mortifying it instead. DAPM */
-                   if (SvTIED_mg(sv, PERL_MAGIC_tiedelem))
-                       sv_2mortal(sv);
-               }
             }
        }
        else if (PL_op->op_private & OPpDEREF)
@@ -2952,17 +2955,8 @@ PP(pp_aelem)
            PUSHs(lv);
            RETURN;
        }
-       if (PL_op->op_private & OPpLVAL_INTRO) {
-           SV *sv;
+       if (PL_op->op_private & OPpLVAL_INTRO)
            save_aelem(av, elem, svp);
-           sv = *svp;
-           /* If we're localizing a tied array element, this new sv
-            * won't actually be stored in the array - so it won't get
-            * reaped when the localize ends. Ensure it gets reaped by
-            * mortifying it instead. DAPM */
-           if (SvTIED_mg(sv, PERL_MAGIC_tiedelem))
-               sv_2mortal(sv);
-       }
        else if (PL_op->op_private & OPpDEREF)
            vivify_ref(*svp, PL_op->op_private & OPpDEREF);
     }