anchor.diff:          $(this).submit()
         $(this).data('submitting', true)
         false
  -
  
positive.code: $ ->
    $('form#checkout_form_payment').submit (event) ->
      if $(this).data('submitting')
  
negative.code:     else
        braintreeClient = new braintree.api.Client clientToken: braintree.clientToken
        card =
          number: $(braintreeName "number").val()
          expirationDate: $(braintreeName "expiration_date").val().replace(/\s/g, "")
          cvv: $(braintreeName "cvv").val()
          cardholderName: $(braintreeName "cardholder_name").val()
  
        braintreeClient.tokenizeCard card, (err, nonce) =>
          $('input[data-braintree-name=payment_method_nonce]')
  