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• Would you like to work on a fix?

How are you using Babel?

Other (Next.js, Gatsby, vue-cli, ...)

Input code

export type Equals<A1 extends any, A2 extends any> = (<A>() => A extends A2
  ? true
  : false) extends <A>() => A extends A1 ? true : false
  ? true
  : false;

Configuration file name

No response

Configuration

module.exports = {
  presets: [
    [
      '@babel/preset-typescript',
      { isTSX: true, allExtensions: true, disallowAmbiguousJSXLike: true }
    ]
  ],
};

Current and expected behavior

Current

/repl.tsx: Unexpected token, expected "?" (3:30)

  1 | export type Equals<A1 extends any, A2 extends any> = (<A>() => A extends A2
  2 |   ? true
> 3 |   : false) extends <A>() => A extends A1 ? true : false
    |                               ^
  4 |   ? true
  5 |   : false;

Expected

It should parse OK. Both TypeScript and Prettier parse this. Babel was also parsing this correctly a few versions back.

Environment

https://babeljs.io/repl#?browsers=ie%2011&build=&builtIns=false&corejs=3.6&spec=false&loose=false&code_lz=KYDwDg9gTgLgBDAnmYcCiBHArgQwDYDOAPAIICMcoMwAdgCYFw42IA0cJATJSNfY80QA-OAF44AClJCJASjEiSPPgw6cAUHDgB-BFCzBNcAFxwAZvgLB5VWqulyFHZXcbkdegyfOXDW3TD6ft4WhMAA3EA&debug=false&forceAllTransforms=false&shippedProposals=false&circleciRepo=&evaluate=false&fileSize=false&timeTravel=false&sourceType=module&lineWrap=true&presets=env%2Creact%2Ctypescript&prettier=false&targets=&version=7.18.3&externalPlugins=%40babel%2Fplugin-proposal-object-rest-spread%407.6.2&assumptions=%7B%7D

Possible solution

No response

Additional context

No response