Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

How do you test to see if $test equals any item in an array? How would I go about this? I need to iterate over everything in the array and see if $test equals any one of them. 
    unless ( $test eq @array)

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Re: testing against an array
by ccn (Vicar) on Apr 03, 2004 at 20:31 UTC
    There are two ways
    1. simple 
    if( grep{$test eq $_} @array ){
# 
}

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    2. fast 
    foreach (@array) {
  next unless $_ eq $test;
  #here is a match
  # ...
   last;
}

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    You can use '==' instead of 'eq' if the elements are numeric
    Update: The third way can be useful if a great number of testing needed 
    my %test
@test{@array} = ();

foreach (@many_test_values) {
   if (exists $test{$_}) {
     # here is  a match
   }
}

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Re: testing against an array
by dragonchild (Archbishop) on Apr 03, 2004 at 21:29 UTC
    Use Quantum::Superpositions. 
    unless ($test eq any(@array))

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    ------
    We are the carpenters and bricklayers of the Information Age.

    Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

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Re: testing against an array
by McMahon (Chaplain) on Apr 03, 2004 at 20:19 UTC
    How about this: 
     
foreach my $item(@array) { 
   if ($test eq $item) {
       #do something interesting
      }
}

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    Hope that helps....
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[d/l]
      Even shorter:

      if (grep { /^$testforthis$/ } @array {
  #do something
}

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      See grep for more information.
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        Even though the person below me already mentioned this, I felt it needed point out again: You can use any expression with grep, not just a regular expression, so if your testing for equality, use the equality test operator, don't try to coerce a regex in to pretending to be one.

        if( grep $test eq $_, @array )
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Re: testing against an array
by muba (Priest) on Apr 03, 2004 at 20:49 UTC
    or... 'how to loop over an array while checking it's elements in the shortest possible way' :)
    'Short' either meaning 'the least keystrokes' or 'the shortest execution time of the code'
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Re: testing against an array
by matija (Priest) on Apr 03, 2004 at 20:36 UTC
    how about
     
my $ok=0;
map ($_ eq $test?($ok=1):0,@array);
unless ($ok) {....

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