I have an error with phpstorm when I want to change this function
$callback = create_function('$matches', 'return strtoupper($matches[1]);');
by
callback = function('$matches', 'return strtoupper($matches[1]);');
How to resolve that if it's an error.
Thank you.
You shouldn't use create_function(). create_function() uses eval(). eval() is evil.
On a more serious note, eval() (and thus create_function()) has big security issues. If you're on PHP 5.3 or higher, you should use native anonymous functions instead, in this case:
$callback = function($matches) {
return strtoupper($matches[1]);
}
For reference: Anonymous functions.
Note that create_function has been deprecated as of PHP 7.2.
create_function, the eval is not always evil, but you should have very good reasons for using it (relevant discussion).
eval() isn't always evil, you should just be VERY careful using it whenever user input is involved while using it, or if the user has any chance of manipulating input passend to eval(). If you have the opportunity to use anything else but eval(), use something else. Otherwise, sanitize your inputs :D
function()needs to have a body and any argument definitions need to be variables, not strings. The code above is simply invalid PHP. Are you trying to make an anonymous function? If yes, then here's the documentation about those.