Typoglycemia in Coffeescript

Typoglycemia = () ->
  
  text = arguments[0]
  out = []
  params = arguments[1] or []
  level = params.level or 'soft' # soft|hard
  minChars = params.minChars or 4
  maxChars = params.maxChars or 8
  
  processWord = (_word) ->
    return _word if _word.length < minChars
    return _word if _word.length > maxChars and level is 'soft'
    _word = _word.split('')
    first = [_word.shift()]
    last = [_word.pop()]
  
    i = _word.length
    
    while --i
      j = Math.floor(Math.random() * (i + 1))
      temp = _word[i]
      _word[i] = _word[j]
      _word[j] = temp
      
    _word.unshift first
    _word.push last
    _word.join ''
    
  words = text.split(' ')
  
  for word in words
    out.push processWord word
    
  out.join ' '

Usage:

Typoglycemia "String with multiple words"

yields Snitrg with mlutiple words

Typoglycemia "I couldn't believe that I could actually understand what I was reading The phenomenal power of the human mind According to a research at Cambrigde University, it doesn't matter in what order the letters in a word are, the only important thing is that the first and last letter be in the right place. The rest can be a total mess and you can still read it without a problem. This is because the human mind does not read every letter by itself, but the word as a whole.  Amazing huh? Yeah and I always thought spelling was important. "

yields I cndlo'ut beveile that I cloud aaultlcy understand what I was renaidg The phenomenal pwoer of the hmuan mnid According to a raceersh at Cambrigde University, it dose'nt matetr in waht oedrr the leretts in a word are, the olny important tihng is that the frsit and lsat leettr be in the rghit pacle. The rest can be a tatol mess and you can slitl read it wotiuht a plemorb. Tihs is bcuseae the hmuan mind deos not read evrey lteter by iletsf, but the word as a wolhe. Amanizg hhu? Yaeh and I aawyls thhugot sllenipg was important.

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