operator == method
dynamic operator ==(The equality operator.
The default behavior for all Object
s is to return true if and only if this
and other
are the same object.
Override this method to specify a different equality relation on a class. The overriding method must still be an equivalence relation. That is, it must be:
-
Total: It must return a boolean for all arguments. It should never throw or return
null
. -
Reflexive: For all objects
o
,o == o
must be true. -
Symmetric: For all objects
o1
ando2
,o1 == o2
ando2 == o1
must either both be true, or both be false. -
Transitive: For all objects
o1
,o2
, ando3
, ifo1 == o2
ando2 == o3
are true, theno1 == o3
must be true.
The method should also be consistent over time, so whether two objects are equal should only change if at least one of the objects was modified.
If a subclass overrides the equality operator it should override the hashCode
method as well to maintain consistency.
Source
operator ==(other) { if (other is! JsObject && other is! JSObject) return false; return _identityEquality(this, other); }
© 2012 the Dart project authors
Licensed under the Creative Commons Attribution-ShareAlike License v4.0.
https://api.dartlang.org/stable/1.24.3/dart-js/JsObject/operator_equals.html