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Coffeescript - 'this' is always replaced by '_this' in fat arrow callback


I'm wondering is possible somehow to prevent this keyword to be transformed into _this inside fat arrow callback (=>)?

For example:

class someClass

  someMethod: ->
    $(document).on 'click', '.myclass', (e) =>
      # doing things with right context this, it's ok
      @anotherMethod()
      @oneMoreMethod()

      # but here I need jQuery ``this`` pointing to element
      $el = $ this # this is transformed into ``_this`` :(

Maybe I missed some option or operator?

UPDATE I know about the trick like self = this, but I thought CS has something more elegant..


Solution

  • That's the whole purpose of =>.

    Use $(e.currentTarget) to get a handle to the element that would have been this. This is not the same as $(e.target) which you have already rejected.

    And no, CoffeeScript can't have anything more elegant way to handle this. You can only have one context for a function. Bound functions aren't unique to CoffeeScript, they're a feature of JavaScript, and the solution is for the calling code to provide another way of accessing the element, which jQuery does with e.target and e.currentTarget.