transformSync()

A lower-level transform function that returns additional metadata alongside the transformed code.

Signature

TypeScript

function transformSync(
  code: string,
  filepath: string
): TransformResult

Parameters

Parameter	Type	Description
`code`	`string`	TypeScript source code to transform
`filepath`	`string`	File path (used for error reporting)

TransformResult

TypeScript

interface TransformResult {
  // Transformed TypeScript code
  code: string;

  // Source map (JSON string, not yet implemented)
  map?: string;

  // Generated type declarations
  types?: string;

  // Macro expansion metadata
  metadata?: string;
}

Comparison with expandSync()

Feature	`expandSync`	`transformSync`
Options	Yes	No
Diagnostics	Yes	No
Source Mapping	Yes	Limited
Use Case	General purpose	Build tools

Example

TypeScript

import { transformSync } from "macroforge";

const sourceCode = `
/** @derive(Debug) */
class User {
  name: string;
}
`;

const result = transformSync(sourceCode, "user.ts");

console.log(result.code);

if (result.types) {
  // Write to .d.ts file
  fs.writeFileSync("user.d.ts", result.types);
}

if (result.metadata) {
  // Parse and use metadata
  const meta = JSON.parse(result.metadata);
  console.log("Macros expanded:", meta);
}

When to Use

Use transformSync when:

Building custom integrations
You need raw output without diagnostics
You're implementing a build tool plugin

Use expandSync for most other use cases, as it provides better error handling.