From: "Chas. Owens" <[EMAIL PROTECTED]>
> On Dec 18, 2007 4:49 PM, Rob Dixon <[EMAIL PROTECTED]> wrote:
> snip
> > if (grep { not /\.mdb\z/ } @ARGV) {
> > print "All parameters must be MDB files\n";
> > exit;
> > }
> snip
>
> Or in Perl 5.10, coming to stores near you soon*, you can use the
> smart match operator:
>
> @ARGV ~~ /\.mdb\z/
> or die "All parameters must be MDB files"
>
> See smart matching in perldoc perlsyn or
> http://search.cpan.org/dist/perl/pod/perlsyn.pod#Smart_matching_in_detail
>
> * I just checked and in fact it was released yesterday.
I did not install it yet so I can't check but I think you have it
wrong. According to the docs you point to
@ARGV ~~ /\.mdb\z/
is equivalent to
grep /\.mdb\z/, @ARGV
which is true whenever at least one item in the array matches the
regexp. So it would be
@ARGV ~~ /\.mdb\z/
or die "At least one of the parameters must be an MDB file";
Probably not what Rob (or whoever posted the original post) intended.
grep {not <condition>} @ARRAY
is not equivalent to
not grep {<condition>} @ARRAY
not even in boolean context.
@ARGV ~~ /\.mdb\z/
is
any(@ARGV) =~ /\.mdb\z/
not
all(@ARGV) =~ /\.mdb\z/
I think there should have been a !~~ operator as well.
Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
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