Text processing is, unlike an algorithm, is a manually administered sequence of simpler macros that are the pattern-action expressions and filtering mechanisms.
His research interests include all areas of text processing and in particular the transformation of textual corpora in lexical and grammatical representations (i.e. computationally deployable electronic dictionaries and local grammars).
Today regular expressions are widely supported in programming languages, text processing programs (particular lexers), advanced text editors, and some other programs.