Re: check if an element exists in array

[RecursionBane]

For those getting here through the Google terms "element exists in array perl", here's a simple routine I wrote because I wanted something similar to TCL's "lsearch -exact" but with a binary return:

# Checks if a provided element exists in the provided list
# Usage: isInList <needle element> <haystack list>
# Returns: 0/1
sub isInList {
    my $needle = shift;
    my @haystack = @_;
    foreach $hay (@haystack) {
        if ( $needle eq $hay ) {
            return 1;
        }
    }
    return 0;
}

Of course, this should only be used on small haystacks (a few hundred elements at most).

[jdporter]

sub isInList {
  my( $d, $it ) = ( "\0", @_ );
  join( $d, '', @_, '' ) =~ /$d\Q$it\E$d/
}

Caveat: This treats all the values as strings. Input values which are not strings will get stringified! This may or may not yield the desired results.

[RecursionBane]

Elegant! Does Perl automagically return the last modified variable when returning from a subroutine?

[jdporter]

"Last modified variable"? No, it returns the value of the last evaluated expression.