In CoffeeScript, how can you make a function call with anonymous functions as parameters?

The following gives a syntax error related to the anonymous function:

my_function = (f, x, str) ->
  alert str + f(x)

my_function (x) -&开发者_运维技巧gt; 1 + x, 12, "The answer is: "

The following works:

my_function = (f, x, str) ->
  alert str + f(x)

increment = (x) -> x + 1

my_function increment, 12, "The answer is: "

---

my_function ((x) -> x + 1), 12, "The answer is: "

That should fix it.