Php Use() Function for Scope?
I Have Seen Code Like This: Function($Cfg) Use ($Connections) {} but Php. Net Doesn't Seem to Mention That Function. I'm Guessing It's Related to Scope, but...
I have seen code like this:
function($cfg) use ($connections) {}
but php.net doesn't seem to mention that function. I'm guessing it's related to scope, but how?
2 Answers
use is not a function, it's part of the Closure syntax. It simply makes the specified variables of the outer scope available inside the closure.
$foo = 42;
$bar = function () {
// can't access $foo in here
echo $foo; // undefined variable
};
$baz = function () use ($foo) {
// $foo is made available in here by use()
echo $foo; // 42
}
For example:
$array = array('foo', 'bar', 'baz');
$prefix = uniqid();
$array = array_map(function ($elem) use ($prefix) {
return $prefix . $elem;
}, $array);
// $array = array('4b3403665fea6foo', '4b3403665fea6bar', '4b3403665fea6baz');
It is telling the anonymous function to make $connections (a parent variable) available in its scope.
Without it, $connections wouldn't be defined inside the function.
Elena Rostova holds a Master's degree in Public Health Journalism. She covers groundbreaking medical research, holistic wellness trends, mental health awareness, and nutritional science.
