Added a null,singleton,uncons,takeWhile and dropWhile to Data.String

[NightRa]

Added a null,singleton,uncons,takeWhile and dropWhile to Data.String.

I made the takeWhile and dropWhile functions foreign to avoid the unpacking overhead.

[davidchambers]

This line should have a semicolon.

[NightRa]

Didn't know that semicolons are nessesary after function definitions in JS. Thanks.

[davidchambers]

Semicolons are not necessary in most cases, due to automatic semicolon insertion, but we might as well output "correct" code. Also, to clarify, a function statement (as used to define takeWhile above, for example) should not be terminated by a semicolon, whereas a function expression (as used to define the return value of takeWhile) should be.

[NightRa]

Purescript seems to generate semicolons after foreign function statements anyway.

[paf31]

These will not work with dead code elimination turned on. drop might be removed. It would be better to pass a reference to the drop function as a function argument. The same applies to takeWhile.

[joneshf]

Better than that might be to just slice it.

[NightRa]

What would be the best way to add foldl/foldr?
Can't add an instance to Foldable as the element is fixed to be Char..

[paf31]

Thanks!

I think foldl/r can be added as standalone functions (without an instance).