Advanced Template Literal Types

Background

Template literal types enable compile-time string pattern validation, useful for event names, CSS selectors, and API routes.

Problem

Define a type for DOM event handler names (onclick, onkeydown, etc.) using template literal types from a union of event names.

Input

A string that should match the template literal type pattern.

Output

A type-safe string or a compile-time type error.

Sample tests

Input: "onclick"

Expected: Valid EventHandlerName

Your solution

Learning objective

Learn advanced template literal types for compile-time string pattern validation.