You can do this using the pos function when performing matching against a string - This function returns the offset of where the last "m//g" search left off for the variable in question ($_ is used when the variable is not specified).

The following code demonstrates this function in action:

#!/opt/bin/perl

$str = 'The quick brown fox jumps over the lazy dog.';

while ( $str =~ /[aeiou]/ig ) {

    printf(
        "%d %s\n",
        pos( $str ), 
        substr( $str, pos( $str ) - 1 )
    );
    substr( $str, 0, pos( $str ), '' );
}
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If you are already using regexes, @- is all you need. But if you are just looking for a drop-in replacement for index, well, I have used this:

sub regindex {
  my ($str, $rx, $pos) = @_;
  pos($str) = $pos || 0;
  $str =~ /$rx/g or return -1;
  return $-[0];
}
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Thank you all for your help. I am now reading about the pos function.

Richard

Oops. As you demonstrated in your example, $-[0] is what I'm looking for. According to perldoc:

"...$-[0] is the offset into the string of the beginning of the entire match..."

Thanks again.

Richard

See perldoc perlvar for @- and @+.

index() doesn't work with regexen.

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