type-plus

7.6.2 verified Sat Apr 25 auth: no javascript

Type utility library providing over 100 advanced TypeScript types for type-level programming. Current stable version is 7.6.2, released on npm with a moderate release cadence. It offers a wide range of type utilities such as numeric operations, object manipulation, array utilities, logical types, and assertion helpers. Key differentiators include a comprehensive set of type-level functions, support for advanced types like `$Equal`, `$Exact`, `Distributive`, and `AdjustExactOptionalProps`, along with built-in support for ESM and CJS. The library is actively maintained with a beta for v8.0.0 introducing breaking changes like renaming of types and ESM-only mode.

Common errors

error Excessive stack depth comparing types ↓

cause Complex recursive types like `Zeros` cause TypeScript to exceed stack depth.

fix

Upgrade to type-plus@7.6.2+ or avoid using problematic types with deeply nested generics.

error Cannot find module 'type-plus' or its corresponding type declarations ↓

cause Missing or incorrect TypeScript version (<5.4) or package not installed.

fix

Install package: npm install type-plus@latest. Ensure TypeScript >=5.4 for v8.0.0+.

error Property 'IsAny' does not exist on type 'typeof import("type-plus")' ↓

cause Incorrect import style: using `require` or wrong path.

fix

Use proper ES import: import { IsAny } from 'type-plus'.

Warnings

breaking v8.0.0 renames many types: e.g., `Equal` to `$Equal`, `case*` to `$*`, `Exact` options restructured. ↓

fix Upgrade migration: replace old names with new ones (see changelog).

deprecated `NoInfer` and `Failed` types are deprecated in v8.0.0-beta. ↓

fix Remove usage or use alternative types recommended in documentation.

gotcha Incorrect usage of `typesVersions` in package.json caused resolution issues in v8.0.0-beta.5. ↓

fix Update to version 8.0.0-beta.6 or later.

gotcha TypeScript 5.4+ required from v8.0.0-beta.2 onward; earlier versions may fail to load types. ↓

fix Ensure TypeScript version is >=5.4.

gotcha Excessive stack depth errors for some types like `Zeros` in earlier versions. ↓

fix Upgrade to v7.6.2 or later for fix.

Install

npm install type-plus

yarn add type-plus

pnpm add type-plus

Imports

IsAny
wrong
```
import { IsAny } from 'type-plus/esm'
```
correct
```
import { IsAny } from 'type-plus'
```
Package supports ESM and CJS; top-level import works for both.
type-plus
```
import * as tp from 'type-plus'
```
Namespace import to avoid name conflicts.

Equal

wrong

import { $Equal } from 'type-plus'

correct

import { Equal } from 'type-plus'

In v7.x, use `Equal`; v8.0.0 renames to `$Equal`.

Quickstart

Demonstrates basic type-level type guards and array reversal using type-plus in TypeScript.

import { IsAny, IsNever, IsLiteral, IsUnion, Exact, A } from 'type-plus'

// Check types at the type level
type CheckAny = IsAny<any> // true
type CheckNever = IsNever<never> // true
type CheckLiteral = IsLiteral<'hello'> // true
type CheckUnion = IsUnion<string | number> // true

// Exact type comparison
type ExactCheck = Exact<{ a: 1 }, { a: 1 }> // true
type ExactMismatch = Exact<{ a: 1 }, { a: 2 }> // false

// Array utilities
type Reversed = A.Reverse<[1, 2, 3]> // [3, 2, 1]