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Liz Laffitte
Liz Laffitte

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PHP Cheatsheet for Rubyists

This is a quick cheatsheet for every Rubyist struggling to remember PHP syntax.

Variables

Ruby
Variable names can begin with an alphanumeric character or an underscore, but not a number. Local variables don't require any keywords. Variables are case sensitive (name and Name are two different variables). Conventionally, variables begin with a lowercase letter, and snakecase is used for multi-word variable names. You must assign a value to a variable when it is initialized, even if that value is 0, an empty string, or nil.

Instance variables are initialized with the @ symbol, class variables with two @@, and global variables with a $.

name = "Ginny" Name = "Jennifer" p name # "Ginny" p Name # "Jennifer" your_name = "Ted" _energy = nil @@name = "Liz" $tater = "Tot" 
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PHP
PHP variables always start with a dollar sign ($) and all variable declarations (all lines in PHP actually) must end with a semicolon (;). Other than that, PHP and Ruby variables have very similar rules. Variables names can start only with an alphanumeric character or an underscore, never a number. Variables are case sensitive.

However, you can declare a PHP variable without assigning it a value. Also, multi-word variables names can be camel- or snakecase.

<?php $tatertots; $name = "Liz"; $hours_of_sleep = 0; $tatertots = 3; 
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Comments

Ruby
Single line comments begin with a hash.

p "Pay attention to this." #ignore this 
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Multiline comments begin with =begin and end with =end.

p "Print this." =begin Don't print this. Also, don't look at this. It's not pretty enough to be part of Ruby. =end 
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It's very common to see hashes across multiple lines.

p "This is common" #Even though #they are #for single lines #technically 
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PHP
Single line comments start with two forward slashes ( // ). Multi-line PHP comments start with a forward slash and a star (/) and end with a star and a forward slash (/), similar to multiline CSS comments.

<?php echo "This will print to the screen." //But this will be ignored. /* This will also be ignored */ 
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Arrays

Ruby
There are two ways to create an array in Ruby:

my_array = Array.new your_array = [1, 2, 3] 
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PHP
There is a grand total of one way to create an array in PHP:

<?php $this_array = array(1, 2, 3); 
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Top comments (1)

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haelmx profile image
Jorge • Edited

Just like Ruby, with PHP yo can create an array with $this_array = [1, 2, 3];