Reinventing the Parser Generator

on YouTube ↗45m

" summary

Describes a modernization that rewrites PLY into SLY, replacing docstring hacks with real lexer+LALR(1) grammar classes that abuses modern metaclasses and uses guaranteed dictionary ordering, class decorators and type hints. Shows concrete fixes: a 15‑year bug where negative 3 minus 4 parsed wrong, examples of token‑type remapping and on‑the‑fly int conversion, and cleaner no-cache deployment. Works under Python 3.6+ but intentionally bends language internals and breaks IDEs and some tooling.

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" chapters (13)

1. 0:00Start
2. 0:27Reinventing the Parser Generator
3. 0:49Parser Generators
4. 1:38Python Magic Methods
5. 2:10Linguistic Abstraction
6. 6:05C Python Distribution
7. 13:14Ignore Warning Messages
8. 13:54Error Function
9. 19:55Assignment Statement
10. 20:14Print Statement
11. 31:00Types
12. 38:04Precedence Rules
13. 39:12Downsides

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