Callback Functions
Nette\Utils\Callback is a static class, which contains functions for working with PHP callbacks.
Installation:
composer require nette/utils
All examples assume the following class alias is defined:
use Nette\Utils\Callback;
check($callable, bool $syntax=false): callable
Checks that $callable
is valid PHP callback. Otherwise throws Nette\InvalidArgumentException
. If the
$syntax
is set to true, the function only verifies that $callable
has a valid structure to be used as a
callback, but does not verify if the class or method actually exists. Returns $callable
.
Callback::check('trim'); // no exception
Callback::check(['NonExistentClass', 'method']); // throws Nette\InvalidArgumentException
Callback::check(['NonExistentClass', 'method'], true); // no exception
Callback::check(function () {}); // no exception
Callback::check(null); // throws Nette\InvalidArgumentException
toString($callable): string
Converts PHP callback to textual form. Class or method may not exists.
Callback::toString('trim'); // 'trim'
Callback::toString(['MyClass', 'method']); // 'MyClass::method'
toReflection($callable): ReflectionMethod|ReflectionFunction
Returns reflection for method or function used in PHP callback.
$ref = Callback::toReflection('trim');
// $ref is ReflectionFunction('trim')
$ref = Callback::toReflection(['MyClass', 'method']);
// $ref is ReflectionMethod('MyClass', 'method')
isStatic($callable): bool
Checks whether PHP callback is function or static method.
Callback::isStatic('trim'); // true
Callback::isStatic(['MyClass', 'method']); // true
Callback::isStatic([$obj, 'method']); // false
Callback::isStatic(function () {}); // false
unwrap(Closure $closure): callable
Unwraps closure created by Closure::fromCallable
.
$closure = Closure::fromCallable(['MyClass', 'method']);
Callback::unwrap($closure); // ['MyClass', 'method']
closure($callable): Closure
(or closure($classOrObject, $method): Closure
)
Converts PHP callback to object Closure.
$trimmer = Callback::closure('trim');
$trimmer(' hello '); // 'hello'
Since PHP 7.1 you should use native Closure::fromCallable
.
invoke($callable, …$args): mixed
Calls the $callable
, passes the remaining parameters as arguments and returns the returned value.
When is not callable, it throws Nette\InvalidArgumentException
unlike call_user_func
which only
triggers a warning.
$callback = 'trim';
Callback::invoke($callback, ' hello '); // 'hello'
Since PHP 7.0 you should use native $callback($arg, ...)
.
invokeArgs($callable, array $args=[]): mixed
Calls the $callable
with $args
arguments and return its value.
When is not callable, it throws Nette\InvalidArgumentException
unlike call_user_func
which only
triggers a warning.
$callback = 'trim';
Callback::invoke($callback, [' hello ']); // 'hello'
Since PHP 7.0 you should use native $callback(...$args)
.