*ngxVar

Angular developers often use *ngIf="foo$ | async as foo to consume an observable easily in templates. However, this approach does not work if your observable emits a boolean as the ngIf will hide the template when the source observable emits a falsy value.

*ngxVar allows developers to easily consume any observable (or static values) regardless of the type.

Installation

npm i --save ngx-var

Import the module

import { NgxVarModule } from "ngx-var"

@NgModule({
  imports: [NgxVarModule],
})
class AppModule {}

Examples

(Examples taken from tests)

TestComponent

class TestComponent {
  numberObservable$: Observable<number>;
  boolObservable$: Observable<boolean>;
  sampleString = 'aa';
  sampleFunc = (a: number, b: number) => a * b;
}

Use with a single boolean observable

<ng-container *ngxVar="boolObservable$ | async as bool">
    <span>{{bool ? 'true':'false'}}</span>
</ng-container>`

Use with multiple values

<ng-container *ngxVar="{ a: numberObservable$ | async, b: sampleString } as data">
    {{data.a}} {{data.b}}
</ng-container>

• Note: As you can see, sampleString is not an observable value, but can still be used.

Use with let syntax

<span *ngxVar="sampleFunc(5, 5); let data">
    {{data}}
</span>

Development

Running unit tests

Run ng test to execute the unit tests via Karma.

Build

Run ng build to build the project. The build artifacts will be stored in the dist/ directory. Use the --prod flag for a production build.

LICENSE

The MIT License (MIT)

Copyright (c) 2021 Anirudh Varma

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.