fix: newstruct's string operator may be overloaded

Author: Alexander Dreyer

Singular/newstruct.cc

@@ -49,6 +49,36 @@ char * newstruct_String(blackbox *b, void *d)
   else
   {
     newstruct_desc ad=(newstruct_desc)(b->data);
+
+    newstruct_proc p=ad->procs;
+    while((p!=NULL)&&(p->t!=STRING_CMD))
+      p=p->next;
+
+    if (p!=NULL)
+    {
+      leftv sl;
+      sleftv tmp;
+      memset(&tmp,0,sizeof(tmp));
+      tmp.rtyp=ad->id;
+      void * newstruct_Copy(blackbox*, void *); //forward declaration
+      tmp.data=(void*)newstruct_Copy(b,d);
+      idrec hh;
+      memset(&hh,0,sizeof(hh));
+      hh.id=Tok2Cmdname(p->t);
+      hh.typ=PROC_CMD;
+      hh.data.pinf=p->p;
+      sl=iiMake_proc(&hh,NULL,&tmp);
+
+      if (sl->Typ() == STRING_CMD)
+      {
+        char *res = omStrDup((char*)sl->Data());
+        sl->CleanUp();
+        return res;
+      }
+      else
+        sl->CleanUp();      
+    }
+
     lists l=(lists)d;
     newstruct_member a=ad->member;
     StringSetS("");

Tst/Short/bug_newstruct3.res.gz.uu

@@ -0,0 +1,27 @@
+begin 644 bug_newstruct2.res.gz
+M'XL(",(;[$\``V)U9U]N97=S=')U8W0R+G)E<P"=5\MNVSH0W?LK!L)=2`VK
+MBI+U@A$M;K(I4'33[@W%D@.BLF1(<F.CZ+_?(2630]=Q<R,D,<5Y'LZ9H?/M
+M^^/GKP#`"_CR^5]PQF'T&_'DK!;?9DE8`&ZN12M&UULMY"<4!3P=GM=M_3*,
+M_6$SACXN_6$L1VT6%:#72Q_V?;>!2OP40]>O][UH1W=^@T=/*\8^_-(OB0_.
+MXZQS#ZYSA[%$^^P^^E7=>G>.!Q^MW?:PD[LD]<R'W_HE+^PD9+:'X4H6/"!9
+M<.ZC;5^/A[[%:).1X^D8/"(Q^/(BQE@/UW!RBI,G5@1I0OU3#/P2P_.F,NX9
+MZ&6H0X443&B#06L2*:1(PDLD]7%\0S"**[1Q30YH/(HLO$16B>WV+]$B"BVR
+MH4ES$BNBV**EH6:$&6L62S,5Q6&.J.JR`20:FU9(+NHO*:C9MNMW96.,&S&,
+M,!QVN[*M*%FBU#+;OV+!8-.U-8RE:*AQ1M+.?1A.PUCO7$>T2,JF02?&W4Q3
+M9G.=P=*X6P;%31>*AXP2F5%K?MM:EIH1EK*0V(:W;6>F,)MZE@<R7)8X7/0Z
+MOGTL:NX8Q^J5<>(W(7Y3'^1@@?X^8.Z1G3Q6[8TF*<82BW&FYX/6B/%\'^1,
+MPMFE*.0>3:"82R&R2PM/1!@:WS$2%WV2,7A28^_H+;0*TEG-F0=T(1=:$.,Y
+M3T-.BJ:E%B)4V=`/3,IPI07(T;G9)]GTHL4(_-,G^/B^1WO)K;;;G0ZMZ%J'
+M@;/OFA/L&18&!"%_$LSS8>S64L6=30#_>D`>;8#SX!>\X=$&(1T@Z-;?>ZN;
+M!DB\W_\K0FSJFB2^QB/O0@I'ZZ2O0]`ZV6760F=]UDF#UQ/5.MSDEH:$^4?%
+M>JSXAP\8IJJW>/]+$;YK?=*-*1X*P:+KER)V=:9(X>,=-_O)M"]PGZ<KXR<E
+M/K,K70V7I,'/F1L,2$NG^95A8QFKD3#709F:4\D"DT6&A%+,DR5:J1XH))2%
+M_#WK8.?*:DXJ,"OQ=($_9Q5R6!D>UOM[R713%IL1F"569TU?CL16E$]-/:.U
+M&BM+Y9`@2O+M9,19,6^(^T!OYF<;5\H\2YB3,\NY83EJND@?*/MG#VFM;VJW
+M^UGW35=6=>5A7N::SJ]=$_`GHFEC*B&NZ3S/HSE[50HU[F&+?@9X*C<_T&"&
+ML:!):./E)<JK6J2I\\2"NW[I.S2^`IJG%M#T74`G]Q;<C,(5[:;K^WHSXD#%
+M[Q.8^EA73.'7\#&W\M",5OUN%)<'IK@\.!=7G:NPD;Y>5QZ\L:[S9:W=$Z0\
+MB$@>V$4&==N]0-?*.T15^Z7K?PR@#\(NH?807T!^__'Q("&9X0"7_SK-ES#F
+,_\_B/X+A?Q!P#0``
+`
+end

Tst/Short/bug_newstruct3.stat

@@ -0,0 +1,4 @@
+1 >> tst_memory_0 :: 1340873666:3144- exported :3-1-4:x86_64-Linux:lts035:204848
+1 >> tst_memory_1 :: 1340873666:3144- exported :3-1-4:x86_64-Linux:lts035:3100672
+1 >> tst_memory_2 :: 1340873666:3144- exported :3-1-4:x86_64-Linux:lts035:3100672
+1 >> tst_timer_1 :: 1340873666:3144- exported :3-1-4:x86_64-Linux:lts035:10

Tst/Short/bug_newstruct3.tst

@@ -0,0 +1,99 @@
+LIB "tst.lib";
+tst_init();
+
+proc divisor_print(divisor D)
+{
+"Divisor = ("+string(D.den)+") - ("+string(D.num)+")";
+}
+proc divisor_status(divisor D)
+{
+  return ("status");
+}
+proc divisor_test(divisor D)
+{
+  return ("test");
+}
+proc divisor_gcd(divisor D, divisor D2)
+{
+  return ("gcd");
+}
+proc divisor_extgcd(divisor D, divisor D2)
+{
+  return ("extgcd");
+}
+proc divisor_diff(divisor D, divisor D2)
+{
+  return ("diff");
+}
+
+newstruct("divisor","ideal den,ideal num");
+newstruct("formaldivisor","list summands");
+newstruct("pdivisor","list summands, cone tail");
+
+system("install","divisor","status",divisor_status, 4);
+system("install","divisor","test",divisor_test,4);
+system("install","divisor","gcd",divisor_gcd,2);
+system("install","divisor","extgcd",divisor_extgcd,2);
+
+
+system("install","divisor","print",divisor_print,1);
+
+ring r=0,(x,y),dp;
+
+divisor C;
+C.num = ideal(x);
+C.den = ideal(y);
+
+C;
+test(C);
+status(C);
+gcd(C,C);
+extgcd(C,C);
+// -------------------------------------------------------
+newstruct("myunion", "poly p,int i");
+proc to_poly(myunion uni)            
+{                                    
+  return (uni.p);                    
+}                                    
+
+proc to_int(myunion uni)
+{                       
+  return (uni.i);       
+}                       
+
+ring r=0,x,dp;
+
+myunion uni;
+uni.p = x+1;
+uni.i = 17; 
+
+system("install", "myunion", "poly", to_poly, 1);
+system("install", "myunion", "int", to_int, 1);  
+
+poly(uni); // -> x+1
+int(uni);   // -> 17
+
+// ---------------------------------------------------------
+
+newstruct("stringifiable", "int i");
+stringifiable stry;
+stry;
+string(stry);
+
+proc to_str(def arg) { return ("(overloaded)"); }
+system("install", "stringifiable", "string", to_str,1);
+stry;  // print falls back to string
+string(stry);
+
+proc to_str_wrong(def arg) { return (17); }
+system("install", "stringifiable", "string", to_str_wrong,1);
+stry;  // incorrectly converted, fall back to default
+string(stry);
+
+proc printing(def arg) { ("(overloaded)"); }
+system("install", "stringifiable", "print", printing,1);
+
+stry;  // now only print works correctly
+string(stry); // incorrectly converted, fall back to default
+
+tst_status(1);$