Supported Languages

Starting in v0.3.0, symtrace provides first-class AST parsing and structural analysis for 9 programming languages and data formats.

Language Support Matrix

Language	Extensions	Key Entity Identifiers Analyzed
Rust	.rs	function_item, struct_item, enum_item, impl_item, trait_item
JavaScript	.js, .jsx, .mjs, .cjs	function_declaration, class_declaration, method_definition, arrow_function
TypeScript	.ts, .tsx	function_declaration, class_declaration, interface_declaration, type_alias_declaration
Python	.py, .pyi	function_definition, class_definition, async_function_definition
Java	.java	method_declaration, class_declaration, interface_declaration, constructor_declaration
C	.c, .h	function_definition, struct_specifier, enum_specifier, type_definition
C++	.cpp, .hpp, .cc, .cxx, .h++	function_definition, class_specifier, namespace_definition, template_declaration
Go	.go	function_declaration, method_declaration, type_declaration, type_spec
JSON	.json, .jsonc	pair, object, array

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Mixed-Language Repositories

Files with unsupported file extensions are automatically skipped gracefully — zero errors, zero clutter. You can safely run symtrace against any repository regardless of content.

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Language Detection Logic

Language mapping is determined strictly by file extension. There is no runtime shebang parsing or content sniffing, guaranteeing fast and deterministic detection.

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Adding a New Language

New languages are integrated into symtrace using Tree-sitter C grammars:

1. Add the Tree-sitter grammar dependency to Cargo.toml.
2. Define extension mappings in src/language.rs.
3. Configure entity node types and identifier resolution rules in src/ast_builder.rs.
4. Add language test cases to tests/.

See Contributing Guide for details.