Type Support

dtsx provides comprehensive support for various TypeScript type constructs. This page details the supported types and how they are handled.

Basic Types

• Primitive Types: string, number, boolean, null, undefined
• Literal Types: String, number, and boolean literals
• Union Types: Combinations of multiple types
• Intersection Types: Merged types with all properties

Complex Types

Interfaces and Types

interface User {
  name: string;
  age: number;
  email?: string;
}

type UserRole = 'admin' | 'user' | 'guest';

Functions and Methods

function process<T>(input: T): Promise<T>;
interface Processor {
  transform<T>(data: T): T;
}

Classes and Enums

class User {
  constructor(name: string);
  getName(): string;
}

enum UserStatus {
  Active,
  Inactive,
  Pending
}

Generics

interface Container<T> {
  value: T;
  getValue(): T;
}

Advanced Type Features

Conditional Types

type IsString<T> = T extends string ? true : false;

Mapped Types

type Readonly<T> = {
  readonly [P in keyof T]: T[P];
};

Utility Types

• Partial<T>
• Required<T>
• Readonly<T>
• Record<K,T>
• Pick<T,K>
• Omit<T,K>
• Exclude<T,U>
• Extract<T,U>
• NonNullable<T>
• ReturnType<T>
• InstanceType<T>

Type Inference

dtsx provides intelligent type inference for:

• Object literals
• Array literals
• Function return types
• Generic type parameters
• Union types
• Intersection types

Type Augmentation

Support for:

• Module augmentation
• Interface merging
• Declaration merging
• Ambient declarations