h3 Unwrapping async calls with ! (bang)

p A ! postfix to a function call signals to Kaffeine that this is an unwrapped async call masquerading as a normal function call. Kaffeine will recompile it into a normal function call with the follow code wrapping into an async callback:

textarea
  // simple call
  fish = $.get! '/fish'     
  $("stomach").append fish

  // another simple call with implied ()
  ok = stomach.save!        
  meal.complete = ok

This is super useful for simplifying nested asynchronous calls (esp with nodejs) and works nicely in a number of scenarios.

p When does the function unwrapping ‘stop’?

ul
  li At an unmatched right bracket (e.g. the end of a function or arg list)
  li The end of the file
  li Or at the <code>—–</code> operator

textarea
  x = -> {
    result = shoot! user1
    if result, user1.die!
    ---
    result = shoot! user2
    if result, user.die!
    ---
    result = shoot! user3
    if result, user.die!
    ---
  }

h4 @ in bang function calls

p In the case of unwrapped async calls via the bang postfix, @ will actually refer to the outer this.
p Since we can refer to both via this method, binding becomes unnecessary:

textarea
  Class.cacheData = -> {
    d = $.get! "/" 
    @data = d      // outer this
    this.data = d  // inner this
    return @
  }