use Benchmark 'cmpthese';
use Regexp::Common 'whitespace';

my $f = '   this is a string with  spaces  to    remove      ';
cmpthese(-3, {
  'Regexp-Common' => sub { $_=$f; s/$RE{ws}{crop}//g;    },
  'two-s///'      => sub { $_=$f; s/^\s+//; s/\s+$//;    },
  'one-s///'      => sub { $_=$f; s/^\s+|\s+$//g;        },
  's-capture'     => sub { $_=$f; s/^\s*(.*?)\s*$/$1/;   },
  's-capture2'    => sub { $_=$f; s/^\s*(\S+(?:\s+\S+)?)?\s*$/$1/; },
  'm-capture'     => sub { $_=$f; ($_) = /(\S+(?:\s+\S+)?)/;    },
});

##</code><code>##

                 Rate Regexp-Common s-capture one-s/// s-capture2 m-capture two-s///
Regexp-Common   659/s            --      -91%     -93%       -95%      -96%     -97%
s-capture      7002/s          963%        --     -21%       -45%      -59%     -73%
one-s///       8857/s         1244%       26%       --       -30%      -48%     -66%
s-capture2    12699/s         1827%       81%      43%         --      -26%     -51%
m-capture     17179/s         2507%      145%      94%        35%        --     -34%
two-s///      25941/s         3837%      270%     193%       104%       51%       --