Sample:
@Pipe({ name: 'values', pure: false })
export class ValuesPipe implements PipeTransform {
transform(value: any, args: any[] = null): any {
return Object.keys(value).map(key => value[key]);
}
}
It appears that class inheritance is not supported in ES6. Is there an alternative that doesn't require reverse-engineering the super class?
ES6 does have class inheritance. Classes are inherited by extends.
When you use implements you are asking for type checking against an interface. If you want type checking you should be using Typescript - if you don't need type checking then you don't need implements. Using implements doesn't have an effect on the output code — it's just for type checking during compile.
For example in typescript:
class myClass{
public myID:number
constructor(){
}
talk(){
console.log("hi there");
}
}
class newClass {
public myID:number;
talk(){
console.log("Hi from new Class");
}
}
class newClassImplements implements myClass {
public myID:number;
talk(){
console.log("Hi from new Class");
}
}
newClass and newClassImplements both result in exactly the same javascript after compilation. The version with implements just asks the compiler to make sure it has the same interface as myClass if it doesn't you get an error at compilation.
In your sample above ValuesPipe isn't inheriting from PipeTransform it's simply implementing the interface. If you don't need the type checking you should be able to just write the function you want and forget about implementing the interface.
