Translation with tr///

• Translates a class of characters into another class:

  	$cypher =~ tr/a-zA-Z/n-za-mN-ZA-M/;
  

• Returns the number of characters affected, or "" if the substitution didn't succeed.
• Note that a character class here is simply a list of characters that are matched on a one to one basis between the search list and the replacement list.
• If the replacement list is too short, it is padded out by repeating the last character in the search list. If it is null, then it is just a duplicate of the search list:

  	$numcount = $string =~ y/0-9//;	# Counts the number of numbers

  
  
  

  Modifier	Meaning
  /c	Complement the search list
  /d	Delete found but unreplaced characters
  /s	Squash duplicates

• A few examples:

  	$clean =~ tr/a-zA-Z0-9_//cd;	# Remove any non-alphanumeric character
  	$quiet =~ tr/!/./s;		# Wow!!! becomes just plain old Wow.