Re^3: Too much SQL not enough perl

Note that with a little skullduggery, you can make grep short-circuit. Granted, it's still much more clear to use List::Util 'first', and for searching the same candidate list many times, it's more efficient to use a hash.

my @candidates = qw(z y a b c a d a e a f);

foreach my $question ('a', 'm') {

    if (do{{;grep {$_ eq $question ? do {print "Match\n"; last} : 0 }
                  @candidates}})
    {
    print "Found $question\n";
    }

}
[download]

Caution: Contents may have been coded under pressure.

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Re^4: Too much SQL not enough perl by Aristotle (Chancellor) on Oct 10, 2005 at 14:48 UTC
Of course that really just uses grep for its side-effect, and you could just a little less twisted-brainedly say something like `foreach my $question ('a', 'm') { if ( sub { $_ eq $question and return 1 for @candidates; 0; }->() +) { print "Found $question\n"; } }` [download] which is basically an inlined implementation of List::Util’s `first`. Makeshifts last the longest.	[reply] [d/l]
Re^5: Too much SQL not enough perl by Roy Johnson (Monsignor) on Oct 10, 2005 at 14:58 UTC
Of course that really just uses grep for its side-effect No, it uses the return value as well. The interesting thing is that `last` is interpreted as true. Caution: Contents may have been coded under pressure.	[reply] [d/l]
Re^6: Too much SQL not enough perl by Aristotle (Chancellor) on Oct 10, 2005 at 15:24 UTC
No, that’s not it. I admit I don’t (yet?) understand why that happens exactly, but what happens is that the `last` causes grep to return the entire list. Observe: `my @candidates = qw( z y a b c a d a e a f ); foreach my $question ( 'a', 'd', 'm' ) { my @x = do { {; grep { $_ eq $question ? last : 0 } @candidates } +}; print "$question: @x\n"; } __END__ a: z y a b c a d a e a f d: z y a b c a d a e a f m:` [download] Update: <tye> grep works by moving things around on the stack and then reseting the count. you leave early, you get what's on the stack with the original count Makeshifts last the longest.	[reply] [d/l]