No, you cannot write a single function that will do both. You must have some notion of what "equality" means before you can write this function. Say we denote such equality (in English, not in Perl) with the symbol `~'. You'll need to decide e.g.

• '10' ~ 10?
• 'x10' ~ 0?
• '' ~ 0?

It's also not clear from your question if you want the same function to work for finding both numbers in a number list and strings in a string list, or if you'd also like it magically to "do the right thing" when searching for a string in a number list etc.

Consider what you want to do, and then replace your problematic comparison e.g. with one of these:

• "$_" eq "$item"
• 0+$_ == 0+$item
• The same, but <samp>local</samp>ly switching $^W off.

For an all-singing, all-dancing run-time customizable (and slower) solution, pass in a function to perform the comparison:

sub member(&@$) {
  my ($eq, $array, $item) = @_;
  for (@$array) {
    return 1 if $eq->($_, $item)
  }
  return undef;
}
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Finally, why are you trying to circumvent Perl's booleans? The use of things like $TRUE and $FALSE is a bad idea. First, builtins might not return these values, so you end up with 4 different values, and cannot do stuff like "return $a == $b" in the routine you pass to member. The values of TRUE and FALSE aren't going to change in the lifetime of your program; if they do, all your code will fall apart, so it doesn't matter. And note you're still using Perl's booleans, not yours:

... if ($_ eq $item)

... if ($_ eq $item) == $TRUE

... if (($_ eq $item) != $FALSE) eq $TRUE

#!/usr/bin/perl -w
use strict;

my @stuff = ("foo", 1, "3", "5", 8, "jerk", "bummer");
my $test = "1";

foreach(@stuff){
 print "Found!\n" if ("$test" eq "$_");
}
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Actually, that IS how you handle numeric values. Perl is absolutely typeless - meaning that it implicitly stringifies and numifies variables in the right context. Now, numification often gets you 0 which makes alot of things match where you want them not to. However, stringification will usually get matches properly, when comparing two numbers.

ps: Perl 6! $foo =~ @array

Careful, there are unequal strings that are equal as numbers:

$ perl -e'$c="10e0";$d="1e1";print $c == $d,$/'
1
$ perl -e'$c="10e0";$d="1e1";print $c eq $d,$/'

$ perl -e'$c=10e0;$d=1e1;print $c eq $d,$/'
1
$ perl -e'$c=10e0;$d=1e1;print $c == $d,$/'
1
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I think this question is best solved by redesigning it away.

After Compline,
Zaxo

#!/usr/bin/perl -w 
# 
# quick test to match an item in an array


use strict;

my $match = shift ;
my @arr = qw( 2 3 4 5 6 7 foo foo12 12foo 1foo1)  ;

print "match \n" if ( grep(/\b$match\b/, @arr) )  ;
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Personally I would say that as long as the intention is find a single element in a list then grep is not the ideal. grep is more useful when you want to find all the elements in a list that match some criteria. Using it to find one element usually means that grep is doing a whole lot more work than is necessary. (It wont stop once its found the element even if it were the first.)

Yves / DeMerphq
---
Writing a good benchmark isnt as easy as it might look.

sub isListMember {

  my ($array, $item) = @_;   # array ref, item
  for (@{$array}) {
    if (/^\d+$/) {
      return $TRUE if ($_ == $item);
    } else {
      return $TRUE if ($_ eq $item);
    }
  }
  $return $FALSE;
}
[download]

You realise that this only works for integers?

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

"The first rule of Perl club is you do not talk about Perl club."
-- Chip Salzenberg