d3-view/src/directives/types/type.js

import { assign } from "d3-let";
import debounce from "../../utils/debounce";
import sel from "../../utils/sel";

const base = {
  on(model, attrName) {
    var refresh = refreshFunction(this, model, attrName),
      uid = model.uid;

    // DOM => model binding
    this.sel.on(`input.${uid}`, refresh).on(`change.${uid}`, refresh);
  },

  off(model) {
    var uid = model.uid;
    this.sel.on(`input.${uid}`, null).on(`change.${uid}`, null);
  },

  value(value) {
    if (arguments.length) this.sel.property("value", value);
    else return this.sel.property("value");
  }
};

export function createValueType(proto) {
  function ValueType(el) {
    sel(this).el = el;
  }

  ValueType.prototype = assign({}, base, proto);

  return ValueType;
}

export function refreshFunction(vType, model, attrName) {
  return debounce(() => {
    model.$set(attrName, vType.value());
  });
}