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This article covers features introduced in SpiderMonkey 1.8.1

Determine whether two JavaScript values are equal in the sense of the === operator.


// Added in SpiderMonkey 45

JS_StrictlyEqual(JSContext *cx, JS::Handle<JS::Value> v1, JS::Handle<JS::Value> v2,
                 bool *equal);

// Obsolete since JSAPI 39

JS_StrictlyEqual(JSContext *cx, jsval v1, jsval v2, bool *equal);
Name Type Description
cx JSContext * The context in which to perform the conversion. Requires request. In a JS_THREADSAFE build, the caller must be in a request on this JSContext.
v1, v2 JS::Handle<JS::Value> / jsval The value to compare.
equal bool * Out parameter. Receives the comparison result.


JS_StrictlyEqual determines if v1 is strictly equal to v2 under the JavaScript === operator, as specified in ECMA 262-3 §11.9.6. If the comparison attempt was successful, the method returns true and stores the result in *equal; otherwise it returns false.

Comparing jsvals directly in C++, as in v1 == v2, does not produce a meaningful result, since it is possible for two distinct JSStrings or jsdoubles to represent the same string or number.

See Also

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 Contributors to this page: arai, fscholz, Waldo, Jorend
 Last updated by: arai,