The other answers are all cool for arrays, but maybe
using an array is wrong in the first place. Perl has a data
type specialized for fast lookups, the hash (denoted by a
% in front of the variable name). A lookup of an
element in a hash is very fast, while grep and the
likes have to go through the whole array, which is slower.
There are some drawbacks to hashes as well, first, they
require you to change your code and second and more
importantly, a hash dosen't preserve the order of elements
- you can't get the elements back from the hash in the order
you put them into the hash.
If the above drawbacks are no problem with you, you might
want to use the following code :
#!/usr/bin/perl -w
use strict;
my %elements;
my $element = "foo";
# Fill up our hash a bit
foreach ("bla", "blubb", "foo", "bah") {
$elements{$_} = 1;
};
# now check if $element is in our hash :
print "Found '$element'\n" if (exists $elements{$element});
print "D'oh - '$element' not found\n" unless (exists $elements{$elem
+ent});
# You can still get to all elements in %elements :
foreach (keys %elements) {
# but they are in some weird order ...
print "$_\n";
};