PEG.js
PEG.js is a parser generator for JavaScript that creates parsers from parsing expression grammar (PEG) descriptions. It allows developers to define grammars in a declarative format and automatically generates efficient parsers that can be used in Node.js or browser environments. The tool is particularly useful for building custom languages, data formats, or complex text processing tasks.
Developers should learn PEG.js when they need to create parsers for domain-specific languages, configuration files, or custom data formats in JavaScript projects. It is ideal for tasks like syntax highlighting, code analysis, or implementing interpreters, as it provides a more readable and maintainable alternative to hand-written parsers or regex-based solutions. Use cases include building custom query languages, parsing log files, or creating tools for code generation.