Looking for more information on how to do PHP the right way? Check out PHP: The Right Way

Freek Van der Herten:
Method overloading is possible in PHP (sort of)
Oct 21, 2016 @ 09:33:41

Freek Van der Herten has a post to his site showing how PHP functions can (sort of) be overloaded with the help of a trait from Adam Wathan.

PHP does not support method overloading. In case you’ve never heard of method overloading, it means that the language can pick a method based on which parameters you’re using to call it. This is possible in many other programming languages like Java, C++.

However, with some clever coding, Adam Wathan made a trait, aptly called Overloadable, that makes method overloading possible. It works by just accepting any parameters using the splat operator and then determining which of the given functions must be called according to the given parameters.

He shows how to use the trait in a simple example, defining a single "bar" function and using the "Overloadable" trait to handle the switching between the methods based on the input variables. You can find more information about the trait and the source for it in this gist over on GitHub.

tagged: method overload trait custom splat operator variable

Link: https://murze.be/2016/10/method-overloading-possible-php-sort/

SitePoint PHP Blog:
Re-Implementing the Range Operator in PHP
Mar 09, 2016 @ 12:21:08

The SitePoint blog has a new post that revisits a previous tutorial about implementing a custom operator - the "range" operator - natively in PHP itself. In this new article (again, a repost from the article by Thomas Punt) he comes back and refines the implementation a bit to fix some of the issues with the previous version.

In the prequel to this article (hint: make sure you’ve read it first), I showed one way to implement a range operator in PHP. Initial implementations, however, are rarely the best, and so it is the intention of this article to look at how the previous implementation can be improved.

He starts by mentioning some of the drawbacks to the previous implementation, mostly that the computation of the value would only happen at runtime (slower) and not compile time. He then goes through the code from before and shares the updates to make that allow this compile-time option to work on the lexer, parser and adding in new code for the compilation stage. Finally he makes the updates the Zend VM to allow for these changes to take effect.

tagged: reimplement range operator tutorial source update

Link: http://www.sitepoint.com/re-implementing-the-range-operator-in-php/

SitePoint PHP Blog:
Implementing the Range Operator in PHP
Mar 07, 2016 @ 12:55:47

The SitePoint PHP blog has a new tutorial posted (a repost from this article used with permission) about implementing a new operator in the PHP core language: a "range" operator. This operator allows the definition of a range of values (integer/float) as an internal PHP representation.

In the post below, Thomas Punt implements the range operator in PHP. If you’ve ever been interested in PHP internals and adding features to your favorite programming language, now’s the time to learn! This article will demonstrate how to implement a new operator in PHP. The following steps will be taken to do this: updating the lexer, updating the parser, updating the compilation stage and updating the Zend VM. This article therefore seeks to provide a brief overview of a number of PHP’s internal aspects.

He starts with a look at the range operator and how the intended functionality would work (including when the errors would be thrown). He then goes through the steps listed above and makes additions to the source, complete with the C code to make each change. The article is not only a good look at how to add a custom operator but also gives a good overview of the internals of PHP and how things fit together.

tagged: range operator implementation language c thomaspunt tutorial

Link: http://www.sitepoint.com/implementing-the-range-operator-in-php/

Lorna Mitchell:
New in PHP 7: null coalesce operator
Sep 30, 2015 @ 10:51:52

Lorna Mitchell has a post to her site talking about a new addition to PHP in the upcoming major release of PHP 7 - the null coalesce operator. Despite its slightly confusing name, the operator is very handy for certain use cases with the ternary syntax.

Not the catchiest name for an operator, but PHP 7 brings in the rather handy null coalesce so I thought I'd share an example. In PHP 5, we already have a ternary operator, which tests a value, and then returns the second element if that returns true and the third if it doesn't. [...] There is also a shorthand for that which allows you to skip the second element if it's the same as the first one.

[...] In PHP 7 we additionally get the ?? operator which rather than indicating extreme confusion which is how I would usually use two question marks together instead allows us to chain together a string of values.

She includes an example of this new operator in use, chaining together a simple expression and showing the resulting output. It's a little confusing at first, but then if you remember it reads left to right it clears it up a bit.

tagged: null coalesce operator php7 feature example

Link: http://www.lornajane.net/posts/2015/new-in-php-7-null-coalesce-operator

The Ternary Operator in PHP
May 29, 2015 @ 11:41:44

If you're relatively new to the PHP language, there's an interesting "shorthand" method for evaluation that you may not know about. In this new tutorial from NetTuts.com they show you this handy method - the ternary operator.

The ternary operator allows us to simplify some PHP conditional statements. We'll see how it can be used, with test-driven development and refactoring, to simplify code.

While the tutorial is largely a screencast, they do provide a quick summary of what the operator is mainly used for and an example for quick reference.

tagged: ternary operator tutorial screencast introduction evaluation

Link: http://code.tutsplus.com/tutorials/the-ternary-operator-in-php--cms-24010

Lorna Mitchell:
PHP 5.6 and the Splat Operator
Mar 17, 2014 @ 09:05:36

Lorna Mitchell has a new post to her site looking at a feature of the upcoming PHP 5.6 release, the splat operator (three ellipsis...).

We have a couple of new features coming in to PHP 5.6 with names that sound much less exciting than the features they actually represent: "variadic functions" sound positively academic, and "argument unpacking" isn't exactly catchy. However they both use a new operator in PHP which looks like an elipsis (three dots ...) and is referred to as either the splat operator or the scatter operator. I included them in a recent version of my "Upgrading PHP" talk so I thought I'd share the examples here too in case anyone is interested.

She includes an example of it being used in a variadic function, one that lets you define an optional number of parameters without having to resort to func_get_args. She also talks about "argument unpacking" or the passing in of an array of values with the splat to have it handled like a string. An example with the mail function is included.

tagged: php56 splat operator variadic function argument unpacking

Link: http://www.lornajane.net/posts/2014/php-5-6-and-the-splat-operator

Array Operators in PHP: Interesting but Less Spoken
Jul 01, 2013 @ 10:56:43

On PHPMaster.com there's a new tutorial about array operators in PHP, more so how the usual operators interact with arrays.

Operators in PHP can be organized into seven different categories: arithmetic, assignment, bitwise, comparison, error control, execution, incrementing/decrementing, logical, string, array, and type operators. This article details working with array operators, but also covers how some of the other operators work when used with arrays.

They talk about the operators for:

  • array union (plus)
  • equality (double equals)
  • identity (triple equals)

They also talk briefly about some of the other PHP operators with arrays (like subtraction, multiplication and division) and some of the conversions that PHP does when they're used.

tagged: array operator union equality identity other tutorial

Link: http://phpmaster.com/array-operators-in-php-interesting-but-less-spoken

Base Converting and Binary Operators
Apr 18, 2013 @ 11:44:05

On PHPMaster.com there's a new tutorial from Timothy Boronczyk focusing on the binary operators in PHP and using them to do some base conversions.

This article discusses PHP’s binary operators and how to convert between different counting systems. Most programming books and articles only dedicate a page or two to such topics, and although using the operators is really quite simple, there’s a fair amount of background knowledge one must have to use them correctly. Instead of giving the same bare-bones treatment that every other reference gives, I’ll first provide you the necessary background in number theory. Armed with that knowledge, you’ll be able to understand the binary counting system and base conversions… and familiarity with binary digits is the key to successful use of the binary operators!

As promised he starts off with some number theory complete with illustrations about base-10 and how the values fit into "buckets" of data. He compares this to base-2 (binary) and only then starts getting into the conversion functions. He shows the usage of things like decbin and dechex to modify the values as well as the use of bitwise and binary operators.

tagged: converting binary bitwise operator tutorial numbertheory

Link: http://phpmaster.com/base-converting-and-binary-operators

Sherif Ramadan:
How to Write an Operator Precedence Parser in PHP
Jan 21, 2013 @ 11:21:22

Sherif Ramadan has a post looking at creating a better operator precedence parser in PHP. His example is a fully PHP implementation that takes equation strings and evaluates them to create the result.

Operator precedence parsers are very simple on the surface. So don’t feel in the least bit intimidated, because by the time you’ve read through this I hope to have you walk away with a solid foundation on how to write your very own operator precedence parser. The goal is to understand how to solve the problem of operator precedence parsing, and not necessarily to write your own parser. Learning how the problem can be solved is the most important thing to take away from this article.

He starts with an introduction to the concepts behind "operator precedence" including processing order and grouping. He also mentions infix and postfix (RPN) notations for handling different formats of equations. He used the "Shunting-yard Algorithm" and how it relates to handling the different parts of the equation, one at a time, in the correct order. He rest of the post is dedicated to the details of the execution in the tool, including code examples and the tokenization of the strings passed into it.

tagged: operator precedence parser string token shuntingyard algorithm


How and When do you use Bitwise?
Apr 06, 2012 @ 10:30:32

In this new question to Reddit, there's a question about the usage of bitwise operators - when they might come in useful.

As I get deeper into PHP I notice some lower level functionality that looks like it could be interesting, maybe even useful. I'm trying (other than switching the hex value of a color) to figure out when Bitwise operators might come in handy. Any real world examples?

Responses to the post mention a few cases they'd be useful in - handling permissions, route matching and error reporting. You can find out more about bitwise operators in PHP the PHP manual.

tagged: bitwise usage opinion operator