If it is speed you are after, you can always put on your C hat: 

use Benchmark;
use Inline C;

timethese (1000000, {
'regex'  => q{
  my $foo = "test    ";
  $foo =~ s/\s+$//;
},
'inline' => q{  
  my $foo = "test    ";
  rmsp($foo);
}
});
  
__END__
__C__
void rmsp(char * str) {
  int i = strlen(str) - 1; 
  while( i >= 0 && str[i] == ' ' ) {
    str[i--] = '\0';
  }
}

[download]


Results: 
Benchmark: timing 1000000 iterations of inline, regex...
    inline:  4 wallclock secs ( 4.39 usr +  0.03 sys =  4.42 CPU)
     regex:  8 wallclock secs ( 6.84 usr +  0.03 sys =  6.87 CPU)

[download]

In reply to Re: Removing Trailing Whitespace: Multiple ways. by perlmonkey
in thread Removing Trailing Whitespace: Multiple ways. by DeaconBlues

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