@thalesrc/extra-ts-types

Extra TypeScript utility types for advanced type manipulation and better type safety.

Installation

npm install @thalesrc/extra-ts-types

yarn add @thalesrc/extra-ts-types

pnpm add @thalesrc/extra-ts-types

Usage

import { AnyFunction, PartialSome, Join, Tail } from '@thalesrc/extra-ts-types';

// For polyfills (like URLPattern)
import '@thalesrc/extra-ts-types/polyfills';

API

AnyFunction

A utility type that represents any function with any number of arguments and any return type.

// Example usage
function callFunction(fn: AnyFunction) {
  return fn();
}

const myFunction = (a: number, b: string) => `${a}: ${b}`;
callFunction(myFunction); // Works with any function

ConstructorType<T>

Extracts the constructor type from an interface or class type.

// Example usage
class MyClass {
  constructor(public value: string) {}
}

type MyConstructor = ConstructorType<typeof MyClass>;
// MyConstructor is: new (value: string) => MyClass

DeepestValue<T, K>

Gets the deepest type of a nested object by following a specific key path.

// Example usage
type NestedObject = {
  data: {
    data: {
      data: string;
    };
  };
};

type Result = DeepestValue<NestedObject, 'data'>;
// Result is: string

DeepestObject<T, K>

Gets the deepest object of a nested object by following a specific key path.

// Example usage
type NestedObject = {
  data: {
    data: {
      value: string;
      other: number;
    };
  };
};

type Result = DeepestObject<NestedObject, 'data'>;
// Result is: { value: string; other: number; }

Join<T, Sep>

Joins a union of strings with a separator, creating all possible combinations.

// Example usage
type Colors = 'red' | 'blue' | 'green';
type ColorCombinations = Join<Colors, '-'>;
// Result includes: "red" | "blue" | "green" | "red-blue" | "red-green" | "blue-red" | "blue-green" | "green-red" | "green-blue" | ...

type SimpleJoin = Join<'x' | 'y'>;
// Result: "x" | "y" | "x,y" | "y,x"

PartialSome<T, K>

Makes some properties of an object optional while keeping others required.

// Example usage
interface User {
  id: number;
  name: string;
  email: string;
  age: number;
}

type UserWithOptionalContact = PartialSome<User, 'email' | 'age'>;
// Result: { id: number; name: string; email?: string; age?: number; }

Tail<X>

Omits the first element of a tuple type, returning the rest.

// Example usage
type Numbers = [1, 2, 3, 4, 5];
type RestNumbers = Tail<Numbers>;
// Result: [2, 3, 4, 5]

type Args = [string, number, boolean];
type RestArgs = Tail<Args>;
// Result: [number, boolean]

Polyfills

URLPattern (Global Type)

TypeScript type definitions for the URLPattern Web API, which provides pattern matching for URLs.

// Import all polyfills
import '@thalesrc/extra-ts-types/polyfills';

// Or import URLPattern specifically
import '@thalesrc/extra-ts-types/polyfills/url-pattern';

// Now URLPattern is available in the global scope
const pattern = new URLPattern({ pathname: '/books/:id' });
const result = pattern.exec('https://example.com/books/123');
console.log(result?.pathname.groups.id); // '123'

// Test if a URL matches
if (pattern.test('https://example.com/books/456')) {
  console.log('URL matches!');
}

Interfaces:

• URLPattern - Main interface with test() and exec() methods
• URLPatternInit - Initialization options for creating patterns
• URLPatternResult - Match results including all URL components and captured groups
• URLPatternComponentResult - Matched text and groups for individual URL components

Use Cases

• Function Type Safety: Use AnyFunction for generic function parameters
• Constructor Patterns: Extract constructor types with ConstructorType
• Deep Object Navigation: Work with nested structures using DeepestValue and DeepestObject
• String Combinations: Generate all possible string combinations with Join
• Flexible Interfaces: Create partially optional interfaces with PartialSome
• Tuple Manipulation: Work with tuple types using Tail
• URL Pattern Matching: Use URLPattern polyfill types for type-safe URL routing and matching

Contributing

This package is part of the Thalesrc monorepo. Contributions are welcome!

License

MIT © Thalesrc

Homepage

Visit extra-ts-types.thalesrc.com for more information and examples.