lark-parser/lark 0.8.0

Lark v0.8 - Better LALR and other improvements

on GitHub

- Better LALR

The biggest change to this release is a new LALR engine, that is capable of dealing with a few edge cases that the previous parser couldn't.

This parser is supposed to be fully backwards-compatible with the previous one, but that is hard to verify!

Thank you, @Raekye, for this great contribution to Lark!

For more details, see issue #418

- Transformers now visit tokens, as well as rules (an alternative to lexer_callbacks)

Transformer now visit tokens, in addition to rules.

Simply define a method with the correct name (uppercase, of course), and the transformer will visit your tokens before the rules that contain them.

It's possible to disable this, for backwards compatibility, or for the slight performance gain.

- Other Changes

• Added visit_topdown methods to Visitor classes

• Lark now allows line comments in its rule definitions

• Better error messages

• Improvements to documentation

• Bugfixes

• maybe_placeholders is now the default (backwards-incompatible)** (REVERTED in 0.8.1)