Hello,
On 11/2/07, Christian Maeder
Iavor Diatchki wrote:
Hi, I have always wondered about the usefulness of the "withKey" functions because the key is one of the arguments that the programmer is passing anyway, so they already know its value. [...] Does anybody have other uses of the "withKey" functions? -Iavor
The WithKey-variants are used where a new value is computed from an old one and when this function also needs to consider the key.
At least filterWithKey and foldWithKey are very useful.
I was referring to the insert,update,adjust functions where the key is already one of the arguments to the function. For the various traversals having a WithKey version makes sense.
PS: as for the bug, I would just fix it (i.e., send a patch)
Which implementation do you consider buggy? IntMap or Map?
(or may just document it as inconsistent)
I think that the two should have the same behaviour. To me, the implementation that returns the _old_ value seems more useful. -Iavor