Class Signal<T, U>

A concrete implementation of ISignal.

import { ISignal, Signal } from '@lumino/signaling';

class SomeClass {

  constructor(name: string) {
    this.name = name;
  }

  readonly name: string;

  get valueChanged: ISignal<this, number> {
    return this._valueChanged;
  }

  get value(): number {
    return this._value;
  }

  set value(value: number) {
    if (value === this._value) {
      return;
    }
    this._value = value;
    this._valueChanged.emit(value);
  }

  private _value = 0;
  private _valueChanged = new Signal<this, number>(this);
}

function logger(sender: SomeClass, value: number): void {
  console.log(sender.name, value);
}

let m1 = new SomeClass('foo');
let m2 = new SomeClass('bar');

m1.valueChanged.connect(logger);
m2.valueChanged.connect(logger);

m1.value = 42;  // logs: foo 42
m2.value = 17;  // logs: bar 17