PHP variable "default value"

You can define it in one script and then require_once that script in your other scripts

You could also just use the ternary operator:

$myVar = isset($var)?$var:$default;

From PHP 7, you can now use the null coalescing operator :

$var ?? $default

that does exactly like your function

Use this concise alternative:

isset($myVar) || $myvar=$default;

The || operator is short circuit, it will not evaluate second operant if the first one be evaluated true.

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