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 the Wolfram Language.
- $PreRead is always applied to each complete input string that will be fed to the Wolfram Language.
- In multiline input with a text‐based interface, whenever each line is terminated, $PreRead is typically applied to the input so far.
- $PreRead is applied to all strings returned by a $SyntaxHandler function.
- $PreRead is applied before InString[n] is assigned.
Basic Examples (3)
Introduced in 1991