Re: [Ocaml-lib-devel] Proposal for new list functions

[Janne H. <jjh...@gm...>]

> Having gone back and read the first message in this thread- the only
> difference between my code and the original proposed code is:
> 1) I shortened some of the variable names (note that this is not
> necessarily good)
> 2) I created an inner loop function, instead of making fold_left_while
> recursive.
>=20
> Otherwise, my code is identical to the code originally posted.

Yep.  I take it now that fold_left_while is OK as it is now.  If we decide
to add it, we should add fold_right_while as well.  If we make it
tail-recursive, it's actually more convenient than fold_left_while.

Skaller suggested split/fold_*_while should take the rest of the list
as an argument to the while-condition predicate.  I don't like that
idea, especially as it's not orthogonal to the already existing
dropwhile and takewhile functions, or pretty much all the other list
functions taking some ('a -> bool) function as a parameter.

I don't have a good name to propose for split.  I'd rather rename
List.split and List.combine to List.unzip and List.zip respectively.
But I'm not sure if changing the stdlib function names is such a good
idea..  Haskell prelude contains "break" function.  It is similar to
the split function I'm proposing.  But if we add functions that can be
found from Haskell's standard library, we should try to make them
behave similarly.

How about the name "separate" instead of "split"?  That is what it's
doing anyway, isolating parts of a list separated by some values.  I
still think "split" a better name for it though.

Best regards,
Janne