Retrieves an object's prototype.
Syntax
bool JS_GetPrototype(JSContext *cx, JS::HandleObject obj, JS::MutableHandleObject protop);
| Name | Type | Description |
|---|---|---|
cx |
JSContext * |
Pointer to a JS context from which to derive runtime information. Requires request. In a JS_THREADSAFE build, the caller must be in a request on this JSContext. |
obj |
JS::HandleObject |
Object for which to retrieve the prototype. |
protop |
JS::MutableHandleObject |
Out parameter. If successful, Receives prototype object of obj. |
Description
JS_GetPrototype retrieves the prototype of a specified object, obj. A prototype object provides properties inherited by similar JS objects. This is the equivalent of Object.getPrototypeOf(obj) from javascript.
If JS_GetPrototype returns false, that signals an exception, which should be handled as usual. Otherwise, it stores a pointer to the prototype or null to *protop and returns true.
To set an object's prototype, use JS_SetPrototype.