John Ky wrote:

Hello,

I have this function here:

...

endsWith :: Eq a => [a] -> [a] -> Bool endsWith suffix list | lengthDifference < 0 = False | otherwise = (drop lengthDifference list) == suffix where lengthDifference = (length list) - (length suffix)

I thinks that's what List.isSuffixOf does.

I like being able to say "abc" `endsWith` "c", but I also like to be able to say map (endsWith 't') ["cat", dog"] but I can't have both.

import List "c" `isSuffixOf` "abc" map ("t" `isSuffixOf`) ["cat", "dog"] --Stephan

Hi John, long `endsWith` short = (reverse short) `isPrefixOf` (reverse long) would be a possibility (and might be slightly more efficient). And this argument order is much better according to the principle of least surprise (a `endsWith` b is naturally interpreted so that b is the suffix). Regarding your "map ..." problem: map (`endsWith` "t") ["cat","dog"] takes two keystrokes more, but preserves meaning in infix application. Cheers, Daniel Am Samstag, 21. Oktober 2006 17:19 schrieb John Ky:

Hello,

I have this function here:

...

endsWith :: Eq a => [a] -> [a] -> Bool endsWith suffix list

| lengthDifference < 0 = False | otherwise = (drop lengthDifference list) == suffix

where lengthDifference = (length list) - (length suffix)

Would this be the preferred function argument order? Or is the reverse (ie. endsWith list suffix) better?

I like being able to say "abc" `endsWith` "c", but I also like to be able to say map (endsWith 't') ["cat", dog"] but I can't have both.

By the way, is there a better way to write this function to be clearer and more efficient?

Thanks

-John