made OP_ITER and OP_NEXT use CObjMethods

examples/iterator.cosmo

@@ -17,6 +17,9 @@ proto Range
     end
 end
 
-for i, x in Range(10) do
+local total = 0
-    print("was " .. i .. ", now " .. x)
+for i, x in Range(1000000) do
+    total = total + i
 end
+
+print("total: " .. total)

src/coperators.h

@@ -36,8 +36,8 @@ typedef enum {
     OP_SETOBJECT,
     OP_GETOBJECT,
     OP_INVOKE,
-    OP_ITER, // if stack[top] is an object, __iter is expected and called, else if stack[top] is a dictionary a dummy iterator object is made (SEE: cosmoV_makeIter())
+    OP_ITER,
-    OP_NEXT, // if stack[top] is an object, __next is expected and called, expecting uint8_t return values. if stack[top] after calling is nil, jump uint16_t
+    OP_NEXT,
 
     // ARITHMETIC
     OP_ADD,

src/cparse.c

@@ -1121,7 +1121,7 @@ static void forEachLoop(CParseState *pstate) {
 
     consume(pstate, TOKEN_DO, "Expected 'do' before loop block!");
 
-    writeu8(pstate, OP_ITER); // checks if stack[top] is iterable and makes an iterable object wrapper for CObjs like CObjDict
+    writeu8(pstate, OP_ITER); // checks if stack[top] is iterable and pushes the __next method onto the stack for OP_NEXT to call
 
     int loopStart = getChunk(pstate)->count;
 

src/cvm.c

@@ -149,15 +149,15 @@ bool call(CState *state, CObjClosure *closure, int args, int nresults, int offse
     if (nres == -1) // panic state
         return false;
 
+    if (nres > nresults) // caller function wasn't expecting this many return values, cap it
+        nres = nresults;
+
     // remember where the return values are
     CValue* results = cosmoV_getTop(state, nres-1);
 
     // pop the callframe and return results :)
     popCallFrame(state, offset);
 
-    if (nres > nresults) // caller function wasn't expecting this many return values, cap it
-        nres = nresults;
-
     // push the return value back onto the stack
     memcpy(state->top, results, sizeof(CValue) * nres); // copies the return values to the top of the stack
     state->top += nres; // and make sure to move state->top to match
@@ -580,6 +580,17 @@ int cosmoV_execute(CState *state) {
                             cosmoV_pushValue(state, val);
                             cosmoV_pushValue(state, cosmoV_newObj(obj));
                             cosmoV_call(state, 1, 1); // we expect 1 return value on the stack, the iterable object
+
+                            StkPtr iobj = cosmoV_getTop(state, 0);
+
+                            if (!IS_OBJECT(*iobj)) {
+                                cosmoV_error(state, "Expected iterable object! '__iter' returned %s, expected object!", cosmoV_typeStr(*iobj));
+                                break;
+                            }
+
+                            CObjObject *obj = (CObjObject*)cosmoV_readObj(*iobj);
+
+                            cosmoV_getObject(state, obj, cosmoV_newObj(state->iStrings[ISTRING_NEXT]), iobj);
                         } else {
                             cosmoV_error(state, "Expected iterable object! '__iter' not defined!");
                         }
@@ -598,25 +609,17 @@ int cosmoV_execute(CState *state) {
                 uint16_t jump = READUINT();
                 StkPtr temp = cosmoV_getTop(state, 0); // we don't actually pop this off the stack
 
-                if (!IS_OBJECT(*temp)) {
+                if (!IS_METHOD(*temp)) {
-                    cosmoV_error(state, "Couldn't iterate over non-iterator type %s!", cosmoV_typeStr(*temp));
+                    cosmoV_error(state, "Expected '__next' to be a method, got type %s!", cosmoV_typeStr(*temp));
                     break;
                 }
 
-                CObjObject *obj = (CObjObject*)cosmoV_readObj(*temp);
+                cosmoV_pushValue(state, *temp);
-                CValue val;
+                cosmoV_call(state, 0, nresults);
 
-                if (cosmoO_getIString(state, obj, ISTRING_NEXT, &val)) {
+                if (IS_NIL(*(cosmoV_getTop(state, 0)))) { // __next returned a nil, which means to exit the loop
-                    cosmoV_pushValue(state, val);
+                    cosmoV_setTop(state, nresults); // pop the return values
-                    cosmoV_pushValue(state, *temp);
+                    frame->pc += jump;
-                    cosmoV_call(state, 1, nresults);
-
-                    if (IS_NIL(*(cosmoV_getTop(state, 0)))) { // __next returned a nil, which means to exit the loop
-                        cosmoV_setTop(state, nresults); // pop the return values
-                        frame->pc += jump;
-                    }
-                } else {
-                    cosmoV_error(state, "Expected iterable object! '__next' not defined!");
                 }
                 break;
             }