typed-inject/src/api/Injectable.ts

Type safe dependency injection framework for TypeScript

import { CorrespondingTypes } from './CorrespondingType.js';
import { InjectionToken } from './InjectionToken.js';

export type InjectableClass<
  TContext,
  R,
  Tokens extends readonly InjectionToken<TContext>[],
> = ClassWithInjections<TContext, R, Tokens> | ClassWithoutInjections<R>;

export interface ClassWithInjections<
  TContext,
  R,
  Tokens extends readonly InjectionToken<TContext>[],
> {
  new (...args: CorrespondingTypes<TContext, Tokens>): R;
  readonly inject: Tokens;
}

export type ClassWithoutInjections<R> = new () => R;

export type InjectableFunction<
  TContext,
  R,
  Tokens extends readonly InjectionToken<TContext>[],
> =
  | InjectableFunctionWithInject<TContext, R, Tokens>
  | InjectableFunctionWithoutInject<R>;

export interface InjectableFunctionWithInject<
  TContext,
  R,
  Tokens extends readonly InjectionToken<TContext>[],
> {
  (...args: CorrespondingTypes<TContext, Tokens>): R;
  readonly inject: Tokens;
}

export type InjectableFunctionWithoutInject<R> = () => R;

export type Injectable<
  TContext,
  R,
  Tokens extends readonly InjectionToken<TContext>[],
> =
  | InjectableClass<TContext, R, Tokens>
  | InjectableFunction<TContext, R, Tokens>;