#!/usr/bin/perl -w
use strict;
use Benchmark;
my $val="      Smart Way    ";

timethese(1000000, {
regex1 => sub {
    my $tmp = $val;
    $tmp =~ s/^\s*(.*?)\s*$/$1/g;
  },
  regex2 => sub {
    my $tmp = $val;
    $val = join (" ",split " ",$val);
  },
  regex3 => sub {
    my $tmp = $val;
    $tmp =~ s/^\s+//;
    $tmp =~ s/\s+$//;
  }
});
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__OUTPUT__
Benchmark: timing 1000000 iterations of regex1, regex2, regex3...
regex1: 6 wallclock secs ( 5.25 usr + 0.00 sys = 5.25 CPU) @ 190512.48/s (n=1000000)
regex2: 2 wallclock secs ( 1.83 usr + 0.00 sys = 1.83 CPU) @ 547045.95/s (n=1000000)
regex3: 2 wallclock secs ( 1.02 usr + 0.00 sys = 1.02 CPU) @ 984251.97/s (n=1000000)