A parser for the Power Query/M language, written in TypeScript. Designed to be consumed by other projects.
A few minimal code samples can be found in example.ts.
If you're planning on parsing static documents then you should use the tryLexAndParse function located in src/jobs.ts. This function attempts to lex a document, pass the results to the parser, and then return the outcome.
If you're planning to perform repeated lexing and parses, such as being a part of a Visual Studi Code extension, then for performance reasons you should avoid the tryLexAndParse helper function. Instead you should create a Lexer instance and as your text changes update the lexer using the public APIs located in src/lexer/lexer.ts. Once you need to parse the document follow the same steps in src/jobs.ts; create a LexerSnapshot and pass the result to the parser.
The parser is a rather naive recursive descent parser with limited backtracking. It mostly follows official specification released in October 2016. Deviations from the specification should be marked down in specification.md
This project uses prettier as the primary source of style enforcement. Additional style requirements are located in style.md.
- Install NodeJS
npm installnpm run-script build
- Install NodeJS
npm installnpm test
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This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.