꘩TS’emekwes

June 8, 2026 · View on GitHub

꘩TS’emekwes A PEG parser generator in TypeScript

꘩TS’emekwes is the Go sibling of 竜TatSu (Python), ⻰OGoPEGo (Go), and 铁修TieXiu (Rust). It is functionally complete and passes the same test suite as its siblings.

Refer to the 竜TatSu documentation for grammar syntax, semantics, and usage. The local SYNTAX.md describes the grammar format.

See the CHANGELOG for a list of present and pending features.

The CLI tool is a great way to explored the features offered by the library:

$ bin/emekwes run --help
Usage: emekwes run [options] <grammar> [inputs...]

execute a grammar against one or more input files

Options:
  -j, --json            output the parse tree in JSON format
  -s, --start <rule>    name of the start rule (default: "start")
  -n, --nproc <number>  number of concurrent workers (default: CPU count)
                        (default: 0)
  -h, --help            display help for command

Global Options:
  -c, --color <when>    control terminal color output (choices: "auto",
                        "always", "never", default: "auto")
  -o, --output <path>   write output to file instead of stdout
  -t, --trace           display a detailed trace of the parsing process
  -q, --quiet           suppress progress bar output
  -V, --version         output the version number

License

Licensed under the Apache License, Version 2.0 (LICENSE or http://www.apache.org/licenses/LICENSE-2.0).

Unless explicitly stated otherwise, any contribution intentionally submitted for inclusion in the work, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.