5 * Contributed by Graham Barr <Graham.Barr@tiuk.ti.com>
6 * The main guts of traverse_isa was actually copied from gv_fetchmeth
10 isa_lookup(HV *stash, char *name, int len, int level)
20 if(strEQ(HvNAME(stash), name))
24 croak("Recursive inheritance detected");
26 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, FALSE);
28 if (gvp && (gv = *gvp) != (GV*)&sv_undef && (hv = GvHV(gv))) {
30 SV** svp = (SV**)hv_fetch(hv, name, len, FALSE);
31 if (svp && (sv = *svp) != (SV*)&sv_undef)
35 gvp = (GV**)hv_fetch(stash,"ISA",3,FALSE);
37 if (gvp && (gv = *gvp) != (GV*)&sv_undef && (av = GvAV(gv))) {
39 gvp = (GV**)hv_fetch(stash, "::ISA::CACHE::", 14, TRUE);
43 if (SvTYPE(gv) != SVt_PVGV)
44 gv_init(gv, stash, "::ISA::CACHE::", 14, TRUE);
49 SV** svp = AvARRAY(av);
50 I32 items = AvFILL(av) + 1;
53 HV* basestash = gv_stashsv(sv, FALSE);
56 warn("Can't locate package %s for @%s::ISA",
57 SvPVX(sv), HvNAME(stash));
60 if(&sv_yes == isa_lookup(basestash, name, len, level + 1)) {
61 (void)hv_store(hv,name,len,&sv_yes,0);
65 (void)hv_store(hv,name,len,&sv_no,0);
69 return boolSV(strEQ(name, "UNIVERSAL"));
73 sv_derived_from(SV *sv, char *name)
87 type = sv_reftype(sv,0);
92 stash = gv_stashsv(sv, FALSE);
95 return (type && strEQ(type,name)) ||
96 (stash && isa_lookup(stash, name, strlen(name), 0) == &sv_yes)
112 croak("Usage: UNIVERSAL::isa(reference, kind)");
115 name = (char *)SvPV(ST(1),na);
117 ST(0) = boolSV(sv_derived_from(sv, name));
131 croak("Usage: UNIVERSAL::can(object-ref, method)");
134 name = (char *)SvPV(ST(1),na);
143 pkg = gv_stashsv(sv, FALSE);
147 GV *gv = gv_fetchmethod_autoload(pkg, name, FALSE);
149 rv = sv_2mortal(newRV((SV*)GvCV(gv)));
157 XS(XS_UNIVERSAL_VERSION)
168 sv = (SV*)SvRV(ST(0));
170 croak("Cannot find version of an unblessed reference");
174 pkg = gv_stashsv(ST(0), FALSE);
177 gvp = pkg ? (GV**)hv_fetch(pkg,"VERSION",7,FALSE) : Null(GV**);
179 if (gvp && (gv = *gvp) != (GV*)&sv_undef && (sv = GvSV(gv))) {
180 SV *nsv = sv_newmortal();
190 if (items > 1 && (undef || (req = SvNV(ST(1)), req > SvNV(sv))))
191 croak("%s version %s required--this is only version %s",
192 HvNAME(pkg), SvPV(ST(1),na), undef ? undef : SvPV(sv,na));
200 #undef boot_core_UNIVERSAL
201 #define boot_core_UNIVERSAL CPerlObj::Perl_boot_core_UNIVERSAL
206 boot_core_UNIVERSAL(void)
208 char *file = __FILE__;
210 newXS("UNIVERSAL::isa", XS_UNIVERSAL_isa, file);
211 newXS("UNIVERSAL::can", XS_UNIVERSAL_can, file);
212 newXS("UNIVERSAL::VERSION", XS_UNIVERSAL_VERSION, file);