The Lezer Parser System

The problem of parsing structured text has resisted one-size-fits all solutions for over 60 years. Lezer isn't such a solution either, but it is a very decent parser generator, especially well suited for use in code editors.

Lezer (the Dutch word for reader, pronounced like “laser”) provides a parser generator that outputs JavaScript modules, which can be loaded to parse code into a non-abstract syntax tree. This tree can then be used to do highlighting and basic semantic analysis.




Lezer is open source under an MIT license. It is maintained by the CodeMirror team.

Lezer is being developed on GitHub. Contributions are welcome.

Discussing the project, or asking questions, is best done on the forum. Bugs should be reported through the issue tracker. We aim to be an inclusive, welcoming community. To make that explicit, we have a code of conduct that applies to communication around the project.