#Parser

Use parseSync to turn source text into an AST compatible with ESTree. TypeScript and JSX nodes follow typescript-eslint's AST format. Install the package for your runtime first.

#Parse a program

import { parseSync } from "@swc-next/core";

const { program, diagnostics } = parseSync("const answer = 42;");
console.log(program.type); // Program
console.log(diagnostics); // []

Inspect diagnostics before transforming or printing recovered syntax.

#Parse TypeScript or JSX

Choose the language explicitly:

import { parseSync } from "@swc-next/core";

const result = parseSync("const answer: number = 42;", { lang: "ts" });
console.log(result.program.body[0].type); // VariableDeclaration

Use jsx or tsx for JSX input, and dts for declaration files. Parsing TypeScript preserves its types; it does not compile them away.

#Next steps

Walk the AST or generate code.

See the Parser API for input and output types, language and source type options, comments, diagnostics, and source positions.