javascript - How can I pass a handler function that may not be defined yet or may change at some point? -

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i ask question because feel there cleaner way solve problem using anonymous function wrap call.

    // not work because passes value found      // @ obj.init @ time of binding.        scope.on('anevent', obj.init);      // works because wrapped in anonymous function ,       // obj.init method gets run whatever defined as.      scope.on('anevent', function() { obj.init(); });

i want date method (obj.init) called whenever 'anevent' emitted.

you're not binding variables, you're binding values. raw obj.init bind the value @ moment event handler. can't bind "the variable" , have value re-evaluated later. re-evaluate variable @ time of event firing, indeed straight forward option:

scope.on('anevent', function() { obj.init(); });

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