create thunk from simple function pointers (not an application)

interpreter/code.c

@@ -19,6 +19,16 @@ struct Thunk* exec(Code* expr)
 					exit(-1);
 			}
 			break;
+		case CT_VAR:
+			switch(expr->local_type)
+			{
+				case VAR_FN:
+					return createF(((VarEntry*) expr)->f, 0);
+					break;
+				default:
+					printf("Exec: Unhandled VAR type");
+					exit(-1);				
+			}
 		default:
 			printf("Exec: Unhandled CODE type");
 			exit(-1);		

interpreter/desc.c

@@ -50,7 +50,7 @@ void gen_slices(void* dest, void* forward_ptr, int arity)
 		SliceEntry* slice = (SliceEntry*) dest + sizeof(SliceEntry) * i;
 		slice->base.type = FT_SLICE;
 		slice->base.arity = i;
-		slice->forward_ptr = forward_ptr;
+		slice->forward_ptr = (Desc*) forward_ptr;
 	}
 }
 

interpreter/desc.h

@@ -36,7 +36,7 @@ struct FunEntry
 struct SliceEntry
 {
 	struct Desc base;
-	void* forward_ptr; // FunEntry or ADTEntry
+	Desc* forward_ptr; // FunEntry or ADTEntry
 };
 struct ADTEntry
 {

interpreter/main.c

@@ -23,8 +23,7 @@ int main()
 		
 	// TODO: put it into a special "expression" space, instead of "code"
 
-	//char *exprstream = "VF13 example.Start";
-	char *exprstream = "LI1 ";
+	char *exprstream = "VF13 example.Start";
 	
 	Code* expr = parseTerm(&exprstream);	
 	Thunk* res = exec(expr);

interpreter/thunk.c

@@ -13,6 +13,36 @@ struct Thunk* createI(int i)
 	return thunk;
 }
 
+struct Thunk* createF(Desc* f, int nrargs)
+{
+	// Even if no arguments, still allocate enough space for a forward pointer 
+	Thunk* thunk = (Thunk*) alloc_heap(sizeof(Thunk) + sizeof(Thunk*) * (nrargs > 0 ? nrargs - 1 : 0));
+	
+	Desc* slice = f;
+	if(f->arity > 0)
+	{
+		slice = &(((SliceEntry*) f)[-f->arity].base);
+	}
+	
+	thunk->desc = slice;
+	return thunk;
+}
+
+int printDesc(Desc* f)
+{
+	switch(f->type)
+	{
+		case FT_SLICE:
+			return printDesc(((SliceEntry*) f)->forward_ptr);
+		case FT_FUN:
+			printf("%s", ((FunEntry*) f)->name);
+			return f->arity;
+		default:
+			printf("printDesc: unhandled DESC\n");
+			exit(-1);		
+	}	
+}
+
 void print(Thunk* thunk)
 {
 	if((FunEntry*) thunk->desc == __INT__)
@@ -21,7 +51,12 @@ void print(Thunk* thunk)
 	}
 	else
 	{
-		printf("print: unhandled DESC\n");
-		exit(-1);
+		int arity = printDesc(thunk->desc);
+
+		if(arity > 0)
+		{
+			printf("print: unhandled arity\n");
+			exit(-1);					
+		}
 	}
-}
\ No newline at end of file
+}

interpreter/thunk.h

@@ -19,6 +19,7 @@ struct Thunk
 };
 
 struct Thunk* createI(int i);
+struct Thunk* createF(Desc* f, int nrargs);
 
 void print(Thunk* thunk);