Move running the module fiber into C.

builtin/core.wren

@@ -60,9 +60,7 @@ class Sequence {
 
 class String is Sequence {
   import_(variable) {
-    var result = loadModule_
-    if (result != null) result.call
-
+    loadModule_
     return lookUpVariable_(variable)
   }
 }

src/wren_core.c

@@ -103,9 +103,7 @@ static const char* libSource =
 "\n"
 "class String is Sequence {\n"
 "  import_(variable) {\n"
-"    var result = loadModule_\n"
-"    if (result != null) result.call\n"
-"\n"
+"    loadModule_\n"
 "    return lookUpVariable_(variable)\n"
 "  }\n"
 "}\n"
@@ -1308,6 +1306,13 @@ DEF_NATIVE(string_loadModule)
   // If it returned a string, it was an error message.
   if (IS_STRING(args[0])) return PRIM_ERROR;
 
+  // If it returned a fiber, we want to call it.
+  if (IS_FIBER(args[0]))
+  {
+    AS_FIBER(args[0])->caller = fiber;
+    return PRIM_RUN_FIBER;
+  }
+
   return PRIM_VALUE;
 }
 

src/wren_value.h

@@ -455,6 +455,9 @@ typedef struct
 // Returns true if [value] is a closure.
 #define IS_CLOSURE(value) (wrenIsObjType(value, OBJ_CLOSURE))
 
+// Returns true if [value] is a fiber.
+#define IS_FIBER(value) (wrenIsObjType(value, OBJ_FIBER))
+
 // Returns true if [value] is a function object.
 #define IS_FN(value) (wrenIsObjType(value, OBJ_FN))