• $PreRead is a global variable whose value, if set, is applied to the text or box form of every input expression before it is fed to Mathematica.
• $PreRead is always applied to each complete input string that will be fed to Mathematica.
• In multiline input with a text-based interface, $PreRead is typically applied to the input so far whenever each line is terminated.
is applied to all strings returned by a $SyntaxHandler
• $PreRead is applied before InString[n] is assigned.
• New in Version 2.