# 13.6: Regular Expressions and Parsing

$$\newcommand{\vecs}{\overset { \rightharpoonup} {\mathbf{#1}} }$$ $$\newcommand{\vecd}{\overset{-\!-\!\rightharpoonup}{\vphantom{a}\smash {#1}}}$$$$\newcommand{\id}{\mathrm{id}}$$ $$\newcommand{\Span}{\mathrm{span}}$$ $$\newcommand{\kernel}{\mathrm{null}\,}$$ $$\newcommand{\range}{\mathrm{range}\,}$$ $$\newcommand{\RealPart}{\mathrm{Re}}$$ $$\newcommand{\ImaginaryPart}{\mathrm{Im}}$$ $$\newcommand{\Argument}{\mathrm{Arg}}$$ $$\newcommand{\norm}{\| #1 \|}$$ $$\newcommand{\inner}{\langle #1, #2 \rangle}$$ $$\newcommand{\Span}{\mathrm{span}}$$ $$\newcommand{\id}{\mathrm{id}}$$ $$\newcommand{\Span}{\mathrm{span}}$$ $$\newcommand{\kernel}{\mathrm{null}\,}$$ $$\newcommand{\range}{\mathrm{range}\,}$$ $$\newcommand{\RealPart}{\mathrm{Re}}$$ $$\newcommand{\ImaginaryPart}{\mathrm{Im}}$$ $$\newcommand{\Argument}{\mathrm{Arg}}$$ $$\newcommand{\norm}{\| #1 \|}$$ $$\newcommand{\inner}{\langle #1, #2 \rangle}$$ $$\newcommand{\Span}{\mathrm{span}}$$

FAQ $$\PageIndex{1}$$

How can I work with regular expressions?

Load Vassili Bykov’s RegEx package from: www.squeaksource.com/Regex.html

FAQ $$\PageIndex{2}$$

Where is the documentation for the RegEx package?

Look at the DOCUMENTATION protocol of RxParser class in the VB-Regex category.

FAQ $$\PageIndex{3}$$

Are there tools for writing parsers?

Use SmaCC —the Smalltalk Compiler Compiler. You should install at least SmaCC-lr.13. Load it from www.squeaksource.com/SmaccDevelopment.html. There is a nice tutorial online: www.refactory.com/Software/SmaCC/Tutorial.html.

FAQ $$\PageIndex{4}$$

Which packages should I load from SqueakSource SmaccDevelopment to write parsers?