Oihana PHP

countCallableParam.php

Table of Contents

Functions

countCallableParam()  : int
Returns the number of parameters of a given callable.

Functions

countCallableParam()

Returns the number of parameters of a given callable.

countCallableParam(callable|string|array<string|int, mixed>|object $callable[, bool $useCache = true ]) : int

This function accepts any PHP callable (Closure, invokable object, array [object/class, method], string function name, or static method string) and returns the number of parameters it declares.

Optionally, a cache can be used to avoid repeated reflection lookups for the same callable, which is useful when the callable is repeatedly inspected (e.g., in loops or recursive functions).

Parameters
$callable : callable|string|array<string|int, mixed>|object

The callable to inspect.

$useCache : bool = true

Whether to cache the computed parameter count. Default true.

Tags
throws
InvalidArgumentException

If the callable cannot be resolved or is unsupported.

throws
ReflectionException

If the callable cannot be reflected (rare).

example

Basic usage with a named function

function testFunction($a, $b, $c) }
echo countCallableParam('testFunction'); // 3
example

With a Closure

$fn = function($x, $y) };
echo countCallableParam($fn); // 2
example

With an invokable object

class MyCallable { public function __invoke($a, $b, $c, $d) } }
$obj = new MyCallable();
echo countCallableParam($obj); // 4
example

With a static method

class MyClass { public static function myMethod($x, $y) } }
echo countCallableParam('MyClass::myMethod'); // 2
example

With an object method

class MyClass { public function myMethod($x, $y, $z) } }
$obj = new MyClass();
echo countCallableParam([$obj, 'myMethod']); // 3
author

Marc Alcaraz (ekameleon)

since
1.0.8
Return values
int —

The number of parameters declared by the callable.


        

        
    




    

    

                                

                

                            
    

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