empty space sensitivity in Try It! section

[newswim]

I've noticed that the validator seems very picky about spaces in my code. I'm extremely new to haskell and this could just be my own naivety. But for example,

let (_,(a:_)) = (10,"abc") in a
-- no spaces

validates and prompts the next lesson, whereas

let (_,(a:_)) = (10, "abc") in a
-- spaces

returns the correct value, but doesn't pass the test.