Zen

Zen of Pyparsing

• Don't clutter up the parser grammar with whitespace, just handle it! (likewise for comments)
• Class names are easier to read and understand than specialized typography
• Use operators to implement an embedded parsing DSL:
  • + for And
  • | for MatchFirst
  • ^ for Or
  • ~ for NotAny
  • & for Each (like And, but accepting out of order)
  • - for And with no backtracking
  • << and <<= for Forward
  • ... for SkipTo
  • [...] for ZeroOrMore
• Simple grammars can return lists; complex grammars need named results
• Parsers can do more than just tokenize

Zen of Pyparsing Development

• Grammars should be:
  • easy (and quick) to write
  • easy to read
  • easy to update
• No separate code-generation step (like lex/yacc)
• No forced naming conventions (like PLY)
• Stay Pure Python
• Liberally licensed (MIT license – free for commercial use)