nikic

Why objects (usually) use less memory than arrays in PHP

This is just a small post in response to [this tweet][tweet] by Julien Pauli (who by the way is the release manager for PHP 5.5). In the tweet he claims that objects use more memory than arrays in PHP. Even though it can be like that, it's not true in most cases. (Note: This only applies to PHP 5.4 or newer.)

The reason why it's easy to assume that objects are larger than arrays is because objects can be seen as an array of properties and a bit of additional information (like the class it belongs to). And as array + additional info > array it obviously follows that objects are larger. The thing is that in most cases PHP can optimize the array part of it away. So how does that work?

The key here is that objects usually have a predefined set of keys, whereas arrays don't:

omeinusch

#!/bin/bash
PASS=`pwgen -s 40 1`

mysql -uroot <<MYSQL_SCRIPT
CREATE DATABASE $1;
CREATE USER '$1'@'localhost' IDENTIFIED BY '$PASS';
GRANT ALL PRIVILEGES ON $1.* TO '$1'@'localhost';
FLUSH PRIVILEGES;
MYSQL_SCRIPT

dbalatero

#!/usr/bin/env ruby

class Practice
  def initialize
    @data = {}
    try_to_load_data
  end

  def record_today(minutes)
    @data[key_for(Time.now)] = minutes

nikic

Order of evaluation in PHP

Yesterday I found some people on my [favorite reddit][lolphp] wonder about the output of the following code:

<?php

$a = 1;
$c = $a + $a++;

spivurno

<?php
/**
 * Gravity Wiz // Gravity Forms // Map Submitted Field Values to Another Field
 *
 * Usage
 *
 * 1 - Enable "Allow field to be populated dynamically" option on field which should be populated.
 * 2 - In the "Parameter Name" input, enter the merge tag (or merge tags) of the field whose value whould be populated into this field.
 *
 * Basic Fields

irazasyed

<?PHP

/**
 * Spintax - A helper class to process Spintax strings.
 */
class Spintax
{
    /**
     * Set seed to make the spinner predictable. 
     */

paulgambill

/**
 * Retrieves all the rows in the active spreadsheet that contain data and logs the
 * values for each row.
 * For more information on using the Spreadsheet API, see
 * https://developers.google.com/apps-script/service_spreadsheet
 */
function readRows() {
  var sheet = SpreadsheetApp.getActiveSheet();
  var rows = sheet.getDataRange();
  var numRows = rows.getNumRows();

oshliaer

###Batch import CSV to a Spreadsheet http://stackoverflow.com/questions/17578317

eyecatchup

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DragonBe

PHP conferences 2016

Name	Location	Start Date	End Date	Attending	Speaking
SkiPHP 2016	Salt Lake City, USA	01-14	01-15
PHPBenelux Conference 2016	Antwerp, Belgium	01-29	01-30	X
SunshinePHP 2016	Miami, USA	02-04	02-06	X	X
PHP UK Conference 2016	London, UK	02-18	02-19
Midwest PHP Conference 2016	Minneapolis, USA	03-04	03-05
LoneStarPHP 2016	Dallas, USA	04-07	04-09