niim/pxtest.js

Node Inspect IMproved

#! /usr/bin/env node

const real = [1,2,3,4,5,6,7,8,9, {hello: 'world'}];

var px = new Proxy(real, {
  get: function(target, prop) {
    if (typeof prop === 'symbol')
      return target[prop];

    switch(typeof target[prop]) {
      case 'undefined':
      case 'number':
      case 'string':
      case 'boolean':
      case 'function':
      case 'symbol':
        return target[prop]; /* immutable */
      case 'object':
        return {...target[prop]};
      default:
        throw new Error('I have no idea what to do with', `(${prop})`);
    }
  },
  set: function(target, prop, value) {
    return false;
  }
});

console.log(px.filter((x) => x > 3));
console.log(real);
console.log(px);
console.log(px.splice(1,2));