Angularity

Core
Overview Exceptions Type Container Type-safe Providing
CDK
Overview Breakpoints
API References
core / Function

provide

Generic types:T U

Type-safe factory function for producing NON-multi Provider configs.

See Also

Presentation

function provide(config: ProvideConfig<T, U>): Provider;

Returns

Provider -

a Provider object

Parameters

NameTypeDescription
config
ProvideConfig<T, U>

type-safe configuration object

Example usage

provide({ token: TitleStrategy, useClass: AppTitleStrategy });
provide({ token: TitleStrategy, useExisting: AppTitleStrategy });
// `AppTitleStrategy` have to be assignable to `TitleStrategy`.

declare const SNACKBAR_CONFIG: InjectionToken<SnackbarConfig>;
provide({ token: SNACKBAR_CONFIG, useValue: { ... } });
// Type of `useValue` is inferred as `SnackbarConfig`, enabling autocomplete.

declare const BREAKPOINTS: InjectionToken<BreakpointMap>
provide({ token: BREAKPOINTS, useFactory: (observer = inject(BreakpointObserver)) => observer.observe() });
// Return type of the factory has to match `BreakpointMap`

provide({ token: APP_INITIALIZER, useFactory: () => () => {} });
// Type error. APP_INITIALIZER should be an array of functions, but the return type of the factory is a single function.
// Type '() => void' is not assignable to type 'readonly (() => void | Observable<unknown> | Promise<unknown>)[]'