Using a closure in coffeescript

Question

I'm trying to implement the code from this SO question in coffeescript.

This is what I've got but it doesn't work.

class SomeClass

    initialize: ->

      target = view.$('#finder')

      typewatch = do ->
        timer = 0;
        (callback, ms) ->
          clearTimeout timer
          timer = setTimeout callback, ms

      target.keyup =>
        typewatch @someMethod(target.val()), 1000


    someMethod: (arg) ->
      // do something

someMethod gets called without any delay. It seems like setTimeout isn't being called at all.

@elclanrs: That makes a lot of sense and I've update the code accordingly, but my problem persists. — niftygrifty, Dec 25 '13 at 07:05

Jokester · Accepted Answer · 2013-12-25T07:10:35.000

1

@someMethod() grammar does invoke the method immediately.

If you want to "store" a method invocation (roughly, method+this+arguments) in a variable and call it later, use Function.prototype.bind. e.g. typewatch @someMethod.bind(@, target.val()), 1000

BTW as elclanrs mentioned, the setTimeout (->callback) part won't really execute callback.

edited Dec 25 '13 at 07:10

answered Dec 25 '13 at 07:05

Jokester

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Using a closure in coffeescript

1 Answers1