Re: [Chicken-users] hash-table-walk + hash-table-delete!

[Graham Fawcett]

On 3/5/07, Kon Lovett <address@hidden> wrote:
> On Mar 5, 2007, at 11:23 AM, Graham Fawcett wrote:
> >> However I think a '(hash-table-remove! hash-table (-> key value
> >> boolean))' procedure should be added to "extras.scm" just to be
> >> "safe".
> >
> > Could you please explain that signature? I don't know how to interpret
> > your (-> ...) form.
>
> A strict prefix form:
>
> (-> key value boolean) is (key value -> boolean) but should be
> (object object -> boolean) since there are no key & value types.

Thanks. I thought it looked like Haskell, and I wasn't that far off.
:-) Wouldn't it be '(hash-table-remove! (-> hash-table key value
boolean)) ? Or do you write it as you did because the procedure
mutates the hash-table?

And lastly, are you passing both key and value in for correctness'
sake (in lieu of passing in the actual bucket, to which we don't have
a reference in a hash-table-walk), or would your implementation
actually test for equality on both before removing?

Graham