IdeaWell

Project ideas from Hacker News discussions.

Intuiting Pratt Parsing

Original Article

Hacker News Discussion

📝 Discussion Summary (Click to expand)

1. Preference for simple hand‑written parsers

"I just don't feel that formal grammar theory is that important in practice. :^)" — logdahl

2. Value of incremental parsing for editor features

"It's not just speed - incremental parsing allows for better error recovery. In practice, this means that your editor can highlight the code as-you-type, even though what you're typing has broken the parse tree." — fwip

3. Practical concerns about parser generators vs. hand‑crafted parsers

"Production compilers must have robust error recovery and great error messages, and those are pretty straightforward in recursive descent, even if ad hoc." — pklausler

These three themes capture the most common viewpoints in the discussion: a bias toward lightweight, recursive‑descent/Pratt parsers; the practical benefits of incremental parsing for IDE‑style tooling; and the pragmatic trade‑offs between using generic parser generators and writing tailored, error‑recoverable parsers.

🚀 Project Ideas

Pratt Playground#Summary

  • [Interactive online REPL for designing and testing Pratt parsers with live AST and precedence preview.]
  • [Lowers entry barrier for language creators by providing instant feedback without local setup.]

Details

Key Value
Target Audience Language designers, educators, hobbyist programmers
Core Feature Real‑time parser builder with live AST output and configurable operator precedence
Tech Stack React, TypeScript, WebAssembly, optional Node.js backend
Difficulty Medium
Monetization Revenue-ready: Freemium with paid advanced features (e.g., custom operator libraries)

Notes

  • [Hacker News commenters loved Pratt parsing: “Love Pratt parsing! … Super simple technique … sufficient for toy languages.” – logdahl]
  • [Potential for community discussions on building domain‑specific languages and teaching parsing concepts.]

IncrementalParse.js

Summary

  • [Plug‑in library that adds incremental parsing and error‑recovery to JavaScript/TypeScript editors for custom DSLs.]
  • [Keeps syntax highlighting and code completion alive even when the current edit breaks the parse tree.]

Details| Key | Value |

|-----|-------| | Target Audience | Editor extension developers, IDE tooling teams | | Core Feature | Incremental parsing of user‑defined operators with precedence climbing, integrated with Monaco/CodeMirror | | Tech Stack | Rust (via WebAssembly), TypeScript typings, npm packaging | | Difficulty | Medium | | Monetization | Revenue-ready: Subscription per organization ($49 / month) |

Notes

  • [Hacker News highlighted the need for better error recovery: “Incremental parsing allows for better error recovery… your editor can highlight the code as‑you‑type.” – fwip]
  • [Adds practical utility for real‑time editor enhancements and can spark discussion on editor‑level language tooling.]

GrammarGuard

Summary

  • [Web service that validates language grammars, detects precedence conflicts, and suggests optimizations using Pratt‑style analysis.]
  • [Produces visual conflict diagrams to help designers resolve ambiguities quickly.]

Details| Key | Value |

|-----|-------| | Target Audience | Language designers, educators, compiler hobbyists | | Core Feature | Upload EBNF or precedence spec → receive conflict graph and auto‑suggested operator precedence | | Tech Stack | Python (FastAPI), D3.js visualizations, Docker deployment | | Difficulty | High | | Monetization | Revenue-ready: Tiered subscription ($15 / month basic, $49 / month pro) |

Notes

  • [Hacker News users emphasized the value of ambiguity detection: “Language design benefits from parser generators that can point out ambiguities…” – ebiederm]
  • [Potential to spark discussion on simplifying grammar theory and providing practical tooling for language spec verification.]

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