Programming Python, 3rd Edition

21.1. "See Jack Hack. Hack, Jack, Hack" In one form or another, processing text- based information is one of the more common tasks that applications need to perform. This can include anything from scanning a text file by columns to analyzing ...

21.2. Strategies for Parsing Text in Python In the grand scheme of things, there are a variety of ways to handle text processing in Python: Built-in string object expressionsString object method callsRegular expression matchingParser-generator in...

21.3. String Method Utilities Python's string methods include a variety of text-processing utilities that go above and beyond string expression operators. For instance, given an instance str of the built-in string obje...

21.4. Regular Expression Pattern Matching Splitting and joining strings is a simple way to process text, as long as it follows the format you expect. For more general text analysis tasks, Python provides regular expression matching utiliti...

21.5. Advanced Language Tools If you have a background in parsing theory, you may know that neither regular expressions nor string splitting is powerful enough to handle more complex language grammars. Roughly, regular expressions don't ha...

21.6. Handcoded Parsers Since Python is a general-purpose programming language, it's also reasonable to consider writing a handcoded parser. For instance, recursive descent parsing is a fairly well-known technique for analyzing language...

21.7. PyCalc: A Calculator Program/Object To wrap up this chapter, I'm going to show you a practical application for some of the parsing technology introduced in the preceding section. This section presents PyCalc, a Python calculator p...