AngularJS | Directive | Makes an input fall back to a default value in case of being empty.

default_value.coffee

'use strict'

app = angular.module 'app'

app.directive 'defaultValue', ->
  require  : 'ngModel'
  restrict : 'A'
  link     : ($scope, element, attrs, ngModel) ->
    ngModel.$parsers.push (value) ->
      if _.isEmpty value
        value = attrs.defaultValue
        ngModel.$setViewValue value
        ngModel.$render()
      value