Abstract

Kind: Interface

Source: packages/common/interfaces/abstract.interface.ts

Part of: Common

Abstract<T> is a generic interface that describes a constructor-like type with a prototype property of type T. It is useful when APIs need to accept or reference a class definition while preserving the instance type represented by that class.

Properties

Property	Type
`prototype`	`T`

Diagram

mermaid
graph LR
  A[Abstract<T>] --> B[prototype: T]
  C[Class Definition] --> A
  B --> D[Instance Shape T]

Usage

ts
interface Abstract<T> {
  prototype: T;
}

class UserService {
  findUser(id: string): string {
    return `User ${id}`;
  }
}

function getPrototype<T>(type: Abstract<T>): T {
  return type.prototype;
}

const userServicePrototype = getPrototype(UserService);

userServicePrototype.findUser("123");

AI Coding Instructions

Use Abstract<T> when a function or API needs to receive a class-like value and access its instance prototype.
Keep the generic T aligned with the instance type represented by the class or constructor.
Do not assume Abstract<T> guarantees that the value is constructable; it only defines the prototype property.
Prefer constructor interfaces with new (...args) => T when callers must instantiate the provided type.
Ensure classes passed to APIs using Abstract<T> expose a prototype compatible with the expected generic type.

Used by

3 references from 3 files. Each is a place in this repository where the symbol is actually used — go read one rather than trusting an example.

Imported by (3)

InvalidClassScopeException — packages/core/errors/exceptions/invalid-class-scope.exception.ts:6
AbstractInstanceResolver — packages/core/injector/abstract-instance-resolver.ts:12
NestApplicationContext — packages/core/nest-application-context.ts:40