javascript - 让 Coffescript 代码变得干燥

Question

我在coffescript中有两个方法，它们看起来像这样:

amount_calculation_when_unit_price_change = (parent) ->
    $(".unit_price input").bind "keyup change", (e) ->
      unit_price = @value.replace(/\,/g,'.')
      quantity = $(this).closest(parent).find(".quantity input").val().replace(/\,/g,'.')
      discount = $(this).closest(parent).find(".discount input").val().replace(/\,/g,'.') if $('.discount input').length > 1
      if discount == ""
        discount = 0
      discount_type = $(this).closest(parent).find(".discount_type select").val() if $('.discount_type select').length > 1
      value = ((parseFloat(unit_price) * parseFloat(quantity)))
      if discount_type == "Absolute"
        value = value - parseFloat(discount).toFixed(2)
      else if discount_type == "Relative"
        discount_price = value * parseFloat(discount/100).toFixed(2)
        value = value - discount_price
      amount = $(this).closest(parent).find(".amount")
      if value.toString().match(pricePattern)
        amount.html('<br/>' + '$' + "#{(value.toFixed(2))}")
      else
        amount.html('<br/>' + '$' + "0.00")
      calculate_total()

  amount_calculation_when_quantity_change = (parent) ->
    $(".quantity input").bind "keyup change", (e) ->
      quantity = @value.replace(/\,/g,'.')
      unit_price = $(this).closest(parent).find(".unit_price input").val().replace(/\,/g,'.')
      discount = $(this).closest(parent).find(".discount input").val().replace(/\,/g,'.') if $('.discount input').length > 1
      if discount == ""
        discount = 0
      discount_type = $(this).closest(parent).find(".discount_type select").val() if $('.discount select').length > 1
      value = ((parseFloat(unit_price) * parseFloat(quantity)))
      if discount_type == "Absolute"
        value = value - parseFloat(discount).toFixed(2)
      else if discount_type == "Relative"
        discount_price = value * parseFloat(discount/100).toFixed(2)
        value = value - discount_price
      amount = $(this).closest(parent).find(".amount")
      if value.toString().match(pricePattern)
        amount.html('<br/>' + '$' + "#{(value.toFixed(2))}")
      else
        amount.html('<br/>' + '$' + "0.00")
      calculate_total()

就像每个人都看到的那样，有很多重复，这段代码看起来非常难看。如何使这段代码更加 DRY？

Answer 1

尝试这样的事情:

amount_calculation_when_unit_price_change = (parent) ->
  for class in ["unit_price, quantity"]
    values = {}
    $(".#{class} input").bind "keyup change", (e) ->
      values[class] = @value.replace(/\,/g,'.')

...