in reply to Determining if an element in a list

Use the grep function, it searches for a pattern in a @list.
use warnings;
use strict;

my $pattern = '1';
my @list = ( 1,2,'a','b',5,1,1,'t');

# In a scalar context grep will return the total times     # that the 
+pattern was find in @list
# If you use @times = grep(/$pattern/,@list);
# @times will contain the pattern it founds in the array
# in this case @times will be ( 1 , 1 , 1 )

my $times = grep(/$pattern/,@list);
print "The pattern was found $times times";

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Re: Re: Determining if an element in a list
by davorg (Chancellor) on Sep 13, 2001 at 12:39 UTC

    In general, this is a pretty inefficient solution as you're searching the whole list every time. In the worst case you have a very long list and the element you're searching for is the first element.

    Something like thoe following is better:

    my $found;
foreach (@list) {
  if (/$pattern/) {
    $found = 1;
    last;
  }
}

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    But the solutions in the FAQ are even better.

    --
    <http://www.dave.org.uk>

    Perl Training in the UK <http://www.iterative-software.com>

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