init $ tail [1,2,3]
= init (tail ([1,2,3])) -- a la Lisp
Now, functional programming is awesomest at abstractions. What if we could
abstract out "init (tail"?
Then we could write
chopEnds = init (tail
But that looks weird. It's only got the left half of a parens pair!
Does that explain why you should not expect the same result?
A separate question is why the compiler even type-checks "init $ tail" in
the first place. What do you think is going on there?
On Tue, Jan 26, 2021 at 1:16 AM Lawrence Bottorff
I've got this
init $ tail [1,2,3] [2]
and this
chopEnds = init $ tail chopEnds [1,2,3] [1,2]
What happened? Why is it not just init $ tail [1,2,3] ?
This works fine
chopEnds2 = init . tail chopEnds2 [1,2,3] [2]
What am I missing?
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-- -- Kim-Ee