1# Features
2
3## Main Features
4 - Earley parser, capable of parsing any context-free grammar
5   - Implements SPPF, for efficient parsing and storing of ambiguous grammars.
6 - LALR(1) parser, limited in power of expression, but very efficient in space and performance (O(n)).
7   - Implements a parse-aware lexer that provides a better power of expression than traditional LALR implementations (such as ply).
8 - EBNF-inspired grammar, with extra features (See: [Grammar Reference](grammar.md))
9 - Builds a parse-tree (AST) automagically based on the grammar
10 - Stand-alone parser generator - create a small independent parser to embed in your project. ([read more](tools.html#stand-alone-parser))
11 - Flexible error handling by using an interactive parser interface (LALR only)
12 - Automatic line & column tracking (for both tokens and matched rules)
13 - Automatic terminal collision resolution
14 - Standard library of terminals (strings, numbers, names, etc.)
15 - Unicode fully supported
16 - Extensive test suite
17 - MyPy support using type stubs
18 - Python 2 & Python 3 compatible
19 - Pure-Python implementation
20
21[Read more about the parsers](parsers.md)
22
23## Extra features
24
25  - Import rules and tokens from other Lark grammars, for code reuse and modularity.
26  - Support for external regex module ([see here](classes.html#using-unicode-character-classes-with-regex))
27  - Import grammars from Nearley.js ([read more](tools.html#importing-grammars-from-nearleyjs))
28  - CYK parser
29  - Visualize your parse trees as dot or png files ([see_example](https://github.com/lark-parser/lark/blob/master/examples/fruitflies.py))
30
31
32### Experimental features
33  - Automatic reconstruction of input from parse-tree (see examples)
34
35### Planned features (not implemented yet)
36 - Generate code in other languages than Python
37 - Grammar composition
38 - LALR(k) parser
39 - Full regexp-collision support using NFAs
40