crystal-tree-sitter

Crystal bindings for the tree-sitter API.

It works by reading the tree-sitter CLI configuration file to locate where the parsers can be found, then it loads the parsers shared objects at runtime when needed. So any parser available on tree-sitter-cli must be available on Crystal.

This is not to be confused with crystal-lang-tools/tree-sitter-crystal, which is a tree sitter parser for parsing Crystal lang.

Installation

1. Add the dependency to your shard.yml:

   dependencies:
     tree_sitter:
       github: crystal-lang-tools/crystal-tree-sitter
   

2. Run shards install

Usage

API still not stable at all and subject to change. Meanwhile look at the spec tests to guess hwo to use it 😁️.

The code used in the Using Parsers tree-sitter tutorial was ported as a spec test at spec/tree_sitter_spec.cr, the API documentation is being ported as well, not yet on github-pages, but run crystal doc and have fun.

require "tree_sitter"

parser = TreeSitter::Parser.new("crystal")

source = <<-CRYSTAL
class Name
end
CRYSTAL

tree = parser.parse nil, source

query = TreeSitter::Query.new(parser.language, <<-SCM)
(class_def) @class

(constant) @constant
SCM

cursor = TreeSitter::QueryCursor.new(query)
cursor.exec(tree.root_node)

cursor.each_capture do |capture|
  p capture
end

Contributing

1. Fork it (https://github.com/crystal-lang-tools/crystal-tree-sitter/fork)
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request

Contributors

• Hugo Parente Lima - creator
• Margret Riegert - maintainer