# normalize-surface-syntax/src/input
Language readers: parse source code into the surface-syntax IR.
Contains tree-sitter-based readers for TypeScript (`typescript.rs`), JavaScript (`javascript.rs`), Lua (`lua.rs`), and Python (`python.rs`), each feature-gated (`read-typescript`, `read-javascript`, `read-lua`, `read-python`). `mod.rs` re-exports the public entry points. Each reader implements the `Reader` trait and is registered as a static in the global registry.
The JavaScript reader delegates to the TypeScript reader's shared `ReadContext` logic via `read_with_language`, since both grammars use identical node kinds for all JavaScript constructs.
Type annotation handling: TypeScript and Python readers now populate `Param::type_annotation`, `Function::return_type`, and `Stmt::Let::type_annotation` from the parsed source. TypeScript uses `type_annotation` child nodes on parameters and variable declarators, and the `return_type` field on function declarations/arrow functions. Python uses `typed_parameter` nodes (with `type` child) for params and the `return_type` field on `function_definition`. Lua and JavaScript have no type annotations; those fields remain `None`.
Template literal handling: The TypeScript reader now produces `Expr::TemplateLiteral(Vec<TemplatePart>)` for backtick strings instead of lowering them to `Concat` binary operations.
Comment preservation: TypeScript and JavaScript readers convert `comment` nodes to `Stmt::Comment` (line comments with `//` stripped, block comments with `/* */` or `/** */` stripped). Lua reader converts `comment` nodes to `Stmt::Comment` (line `--`, LuaDoc `---`, block `--[[ ]]`). Comments are emitted in the target language's syntax by the writer.