Damian Conway writes:
> I don't object in principle to renaming "grep" to something more self
> explanatory (except for the further loss of backwards compatability
> and historical Unix reference...though that didn't stop us with
> "switch" vs "given" ;-)
But while C<switch> had precedence in computer science in general it
didn't have this in Perl; your Switch module is not used much in Perl 5,
and Perl 6's C<given> is a substantial improvement over the C<switch>
statement in most languages.
Whereas C<grep> is a well-known and well-used Perl 5 function, and this
functionality is not being changed in Perl 6 (other than being available
as a method as well as a function).
> The standard--and self-explanatory--CS term for this operation has
> always been "filter", which is also currently used by Python, Scheme,
> Haskell, and numerous other languages, so *if* we're going to change
> it from "grep", we ought to change it to "filter".
Yes, but C<grep> is a just one type of filter: it's specifically a
filter on elements in a list. By deploying the generic word "filter"
for this specific use we'd be clobbering its use for any other sorts of
filters -- on lines, source code, coffee, whatever.
I have no statistics but I'd guess that C<filter> is a reasonably common
sub or method name in Perl 5 code found in the wild -- much more so than
C<say> or C<given> -- and that it's currently being used to filter many
things other than lists.
The above are not conclusive reasons why we shouldn't rename C<grep> to
C<filter> (I'm not that bothered either way myself), but just some
points to bear in mind and reasons to be cautious.