Removing White Space from the begining and end of Perl Strings

Removing White Space From the Beginning and End of Perl Strings

This is required so frequently that it's worth setting up a standard sub-routine to do it. This example is based on one found in the Perl Cookbook and all I've done is to add a few comments and a call to TraceScript...

sub trim
{
   my @out = @_;
   TraceScript $Paranoid, "trim", "About to trim string";
   TraceScript $Paranoid, "trim", "Untrimmed = " . $_[0];
   for (@out)
   {
       s/^\s+//;          # trim left
       s/\s+$//;          # trim right
   }
   return @out == 1
              ? $out[0]   # only one to return
              : @out;     # or many
}

It makes use of Perl's regular expression processing. There is a speed overhead in calling the regular expression parser but sometimes that's a cost worth bearing, as here, when the simplicity of the code outweighs the price in speed of execution.

To use this just store the result of the call in a suitable variable (or whatever)...

$TrimmedString = trim $UntrimmedString;