Typings — ts-types

This module exports static TypeScript utility types. All declarations are compile-time-only — they produce no runtime code.

Import

import type {
    IObject, IDict, IFunction, IAsyncFunction, IDeepPartial,
    IConstructor, IBasicType, IAdvancedType, IElementOfArray,
    IMaybeAsync, IMaybeArray, IToPromise,
    IfIsAny, IfIsNever, IInstanceOf,
} from '@litert/utils-ts-types';

---

Interface IObject

Source: index.ts

A marker interface representing any object value. Use in generic constraints where object would trigger ESLint's @typescript-eslint/ban-types rule.

interface IObject {}

Example:

function merge<T extends IObject>(a: T, b: Partial<T>): T { ... }

---

Type Alias IDict

Source: index.ts

A lightweight dictionary type. A simplified alias for Record<TKey, T>.

Definition

type IDict<
    T = any,
    TKey extends string | number | symbol = string | number | symbol
> = Record<TKey, T>;

Parameters

Parameter	Default	Description
T	any	The type of values in the dictionary.
TKey	string | number | symbol	The allowed key types.

Example:

const data: IDict<number> = { a: 1, b: 2 };
const typed: IDict<string, string> = { key: 'value' };

---

Type Alias IFunction

Source: index.ts

A utility type representing any function. Use in generic constraints where Function would be too broad.

Definition

type IFunction<
    TArgs extends any[] = any,
    TReturn = unknown
> = (...args: TArgs) => TReturn;

Parameters

Parameter	Default	Description
TArgs	any[]	The argument types tuple.
TReturn	unknown	The return type.

---

Type Alias IAsyncFunction

Source: index.ts

A utility type representing any async function. Use in generic constraints for functions returning Promise.

Definition

type IAsyncFunction<
    TArgs extends any[] = any,
    TReturn = unknown
> = (...args: TArgs) => Promise<TReturn>;

Parameters

Parameter	Default	Description
TArgs	any[]	The argument types tuple.
TReturn	unknown	The resolved value type.

---

Type Alias IDeepPartial

Source: index.ts

A recursive version of the built-in Partial<T> that makes all nested properties optional as well.

Definition

type IDeepPartial<T extends IObject> = {
    [P in keyof T]?: T[P] extends IObject ? IDeepPartial<T[P]> : T[P];
};

Example:

interface IConfig { server: { host: string; port: number }; debug: boolean; }
type IPartialConfig = IDeepPartial<IConfig>;
// { server?: { host?: string; port?: number }; debug?: boolean; }

---

Type Alias IConstructor

Source: index.ts

Represents a class constructor function.

Definition

type IConstructor<T = unknown> = new (...args: any[]) => T;

Parameters

Parameter	Default	Description
T	unknown	The instance type the constructor produces.

---

Type Alias IBasicType

Source: index.ts

A union of all JavaScript primitive types.

Definition

type IBasicType = string | number | boolean | symbol | null | undefined | bigint;

---

Type Alias IAdvancedType

Source: index.ts

A union of all non-primitive (object) types.

Definition

type IAdvancedType = IObject | any[] | IFunction | IConstructor;

---

Type Alias IElementOfArray

Source: index.ts

Extracts the element type from an array type T.

Definition

type IElementOfArray<T extends any[]> = T extends Array<infer U> ? U : never;

Example:

type TItem = IElementOfArray<string[]>; // string
type TNum  = IElementOfArray<number[]>; // number

---

Type Alias IMaybeAsync

Source: index.ts

A value that can be either T or Promise<T>. Useful for return types of functions that may be synchronous or asynchronous.

Definition

type IMaybeAsync<T> = Promise<T> | T;

---

Type Alias IMaybeArray

Source: index.ts

A value that can be either a single T or an array T[]. Useful for function parameters that accept both forms.

Definition

type IMaybeArray<T> = T[] | T;

---

Type Alias IToPromise

Source: index.ts

Wraps T in Promise<T>, unless T is already a Promise type (in which case it is returned unchanged).

Definition

type IToPromise<T> = T extends Promise<any> ? T : Promise<T>;

---

Type Alias IfIsAny

Source: index.ts

A conditional type that resolves to TYes when T is any, and TNo otherwise.

Definition

type IfIsAny<T, TYes, TNo> = 0 extends (1 & T) ? TYes : TNo;

---

Type Alias IfIsNever

Source: index.ts

A conditional type that resolves to TYes when T is never, and TNo otherwise.

Definition

type IfIsNever<T, TYes, TNo> = [T] extends [never] ? TYes : TNo;

---

Type Alias IInstanceOf

Source: index.ts

Extracts the instance type from a constructor type T. This is the inverse operation of IConstructor.

Definition

type IInstanceOf<T> = T extends IConstructor<infer U> ? U : never;

Example:

class MyClass {}
type IMyClassCtor = IConstructor<MyClass>;
type IMyClass = IInstanceOf<IMyClassCtor>; // MyClass