Some Array functions for Objects

objUtils.js

// The functional way
const objUtils = {
  mapProps(obj, mapFn) {
    return Object.entries(obj).reduce((a, [key, value]) => (
      { ...a, [key]: mapFn(value) }
    ), {});
  },

  filterProps(obj, filterFn) {
    return Object.entries(obj).reduce((a, [key, value]) => (
      filterFn(value)
        ? { ...a, [key]: value }
        : a
    ), {});
  },  
};

// The imperative way
const objUtils = {
  mapProps(obj, mapFn) {
    const out = {};
    for (const [key, value] of Object.entries(obj)) {
      out[key] = mapFn(value);
    }
    return out;
  },

  filterProps(obj, filterFn) {
    const out = {};
    for (const [key, value] of Object.entries(obj)) {
      if (filterFn(value)) {
        out[key] = value;
      }
    }
    return out;
  },  
};