如何制作可以过滤字符串和数字值的Scfilter？

Question

Javascript(coffescript):

.filter "scFilter", () ->
  (collection, search) ->
    return collection unless search
    regexp = createAccentRegexp(search)
    doesMatch = (txt) -> (''+txt).match(regexp)
    collection.filter (el) ->
      if typeof el == 'object'
        return true for att, value of el when typeof(value) is 'string' and doesMatch(value) and att isnt '$$hashKey'
      else  
        doesMatch(el)

I wanna change this line " return true for att, value of el when typeof(value) is 'string' and doesMatch(value) and att isnt '$$hashKey' " to make is possible to filter number and string values.

Answer 1

This could be easily answered by fixing the conditional logic, but then it will get difficult to read. Instead I'll show you some nicer ways of expressing the condition which you are running in a loop:

return true for att, value of el when typeof(value) is 'string' and doesMatch(value) and att isnt '$$hashKey'

This is the equivalent of:

for att, value of el
  return true if typeof(value) is 'string' and doesMatch(value) and att isnt '$$hashKey'

The doSomething() for X of/in Y when condition syntax is a shorthand which I would suggest only to use if the function fits on a single line without becoming unwieldy.

The above could be made a little more legible by skipping over any fields which you don't want to check:

for att, value of el
  # first filter out any unwanted values
  continue unless typeof(value) is 'string'
  continue if att is '$$hashKey'
  # Then run you function for checking for matching search terms 
  return true if and doesMatch(value) 

Now to extend it to search for numbers is much easier:

for att, value of el
  # first filter out any unwanted values
  continue unless typeof(value) in ['string', 'number']
  continue if att is '$$hashKey'
  # Then run you function for checking for matching search terms 
  return true if and doesMatch(value) 

Take a look at the little book of coffeescript , specifically the idioms as they explain a lot of how comprehensions work in coffeescript