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PHP PHP Basics (Retired) PHP Datatypes Integers

$1 as a variable

Why can't i make $1 or $2 etc. as a variable in PHP?

4 Answers

You can't start a variable with a number. See the php manual for more references http://php.net/manual/en/language.variables.basics.php

I read the document but is there any logical reason behind doing it?

Chris Shaw
Chris Shaw
26,676 Points

The main reason is simply naming conventions, a large percentage of today's popular languages such as PHP, JavaScript, Ruby etc. all require a variable be started with a valid symbol or letter as that is what their compilers are designed to look for where as a number is a literal value therefore the compiler would see it as invalid code because it's not a name but something that be assigned as an value.

To follow on, it would be flipping confusing to have

5 = 10;

Although this post refers to a language that doesn't require a '$' sign to assign variables, php still follows the same naming convention to avoid confusing both man and machine.

Thanks alot

np