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docs/section-8-code-navigation-systems.md

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+---
+title: Code Navigation Systems
+permalink: code-navigation-systems
+---
+
+# Code Navigation Systems
+
+Tree-sitter can be used in conjunction with its [tree query language](https://tree-sitter.github.io/tree-sitter/using-parsers#pattern-matching-with-queries) as a part of code navigation systems. An example of such a system can be seen in the `tree-sitter tag` command, which emits a textual dump of the interesting syntactic nodes in its file argument. This document exists to provide guidelines on the design and use of tree-sitter concepts to implement such systems.
+
+## Tagging and captures
+
+Code navigation systems using Tree-sitter need to use queries and captures to categorize and label different syntactic nodes, such as functions, built-ins, operators, and variables. A reverse-DNS-style notation is recommendedfor these captures, and provide guidelines below for naming captures of a given syntax node. User applications may extend (or only recognize a subset of) these capture names, but it is desirable to standardize on the names below when supported by a given system or language.
+
+| Category                 | Tag                         |
+|--------------------------|-----------------------------|
+| Class definitions        | `@definition.class`         |
+| Function definitions     | `@definition.function`      |
+| Interface definitions    | `@definition.interface`     |
+| Method definitions       | `@definition.method`        |
+| Module definitions       | `@definition.module`        |
+| Function/method calls    | `@reference.call`           |
+| Class reference          | `@reference.class`          |
+| Interface implementation | `@reference.implementation` |
+
+To communicate the associated identifier inside one of these syntactic classes, capture the identifier within as `@name`.
+
+## `tree-sitter graph`
+
+Coming soon!