dimied

58 bytes of CSS to look great nearly everywhere

When making this website, i wanted a simple, reasonable way to make it look good on most displays. Not counting any minimization techniques, the following 58 bytes worked well for me:

main {
  max-width: 38rem;
  padding: 2rem;
  margin: auto;
}

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:

Object Calisthenics outlines 9 basic rules to apply when performing the exercise:

One level of indentation per method.
Don't use the ELSE keyword.
Wrap all primitives and Strings in classes.
First class collections.
One dot per line.
Don't abbreviate.
Keep all classes less than 50 lines.
No classes with more than two instance variables.

	# php -v
	PHP 5.3.6 (cli) (built: Mar 17 2011 20:58:15)
	Copyright (c) 1997-2011 The PHP Group
	Zend Engine v2.3.0, Copyright (c) 1998-2011 Zend Technologies

	# echo '<?php $s = array(); for($x=0;$x<1000;$x++){ $s[] = array("name"=>"Adam","age"=>35); }; echo memory_get_peak_usage(); ' \| php
	655040

	# echo '<?php $s = array(); for($x=0;$x<1000;$x++){ $o = new ArrayObject; $o->name = "Adam"; $o->age = 35; $s[] = $o;} echo memory_get_peak_usage(); ' \| php
	887984

	<?php
	if(!isset($argv[1])){
	echo "Usage: ".$argv[0]." (number of iterations)\n";
	exit(1);
	}

	/**
	* Arrays to check
	*/
	$tests = array(

	package main

	import (
	"context"
	"fmt"
	"io/ioutil"
	"net/http"
	neturl "net/url"
	"time"
	)

	package main

	import (
	"encoding/json"
	"testing"
	)

	type foo struct {
	ID string `json:"_id"`
	Index int `json:"index"`

	Per https://code.google.com/p/v8/codesearch#v8/trunk/src/runtime.cc


	%CreateSymbol
	%CreatePrivateSymbol
	%CreateGlobalPrivateSymbol
	%NewSymbolWrapper
	%SymbolDescription
	%SymbolRegistry
	%SymbolIsPrivate

	import { delay } from 'ts-timeframe';
	import { OperationRegistry } from 'reliable-caching';

	const operationRegistry = new OperationRegistry('costlyFunction');

	async function simulatedCall(a: number, b: number) {
	// these 3 lines represent our call
	await delay(200);
	console.log(`calculated ${a} * ${b}`);
	return a * b;

	/*
	* curry(fn: Function) => Function
	* Simple implementation of currying a function
	* Drawbacks:
	* - Cannot be reused as stored args is mutable
	* - Cannot use placeholders
	* - Will not check argument overflow
	*/
	function curry(fn) {
	var arity = fn.length; // check the arity of the given function