$text =~ 
  s{         # Substitute
     \A      #   from the beginning of the string
     \s+     #   one or more white space characters
   }{}xms;  # with nothing

$text =~ 
  s{         # Substitute
     \s+     #   one or more white space characters
     \z      #   from the end of the string
   }{}xms;   # with nothing

$text =~ 
  s{         # Substitute
     \s+     #   one or more white space characters
   }{ }gxms; # with one space, anywhere in the string
             # As many times as it occurs
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Modified my code to address multiple white spaces in the middle of the string and remove white space from the front of the string. This is a little more verbose than the previous poster but I tried to comment each piece to explain it better.