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Re: choose! and choose



> Date: Sun, 20 Dec 1992 18:36:53 +0100
> From: Jonathan Bachrach <Jonathan.Bachrach@ircam.fr>
> 
>    Date: Fri, 18 Dec 92 18:09:25 EST
>    From: moon@cambridge.apple.com (David A. Moon)
> 
>    > Date: Fri, 4 Dec 1992 18:12:25 +0100
>    > From: Jonathan Bachrach <Jonathan.Bachrach@ircam.fr>
>    > ...
>    >   I would also like to see the following destructively functions added:
>    >   (define-generic-function choose! (predicate mutable-sequence))
>    >   (define-generic-function choose-by! (predicate test-sequence mutable-value-sequence))
> 
>    I don't understand what you propose these will do.
> 
> They would be more powerful `remove!' functions that take a general
> predicate instead of an element to remove (as in `remove!').  They
> would mutate the mutable-sequence such that only the ``chosen''
> elements remain.  They return the mutated argument.

Now I see what you mean.  That seems like a reasonable idea.