(PHP 7)
ReflectionFunctionAbstract::getReturnType — Gets the specified return type of a function
Gets the specified return type of a reflected function.
This function has no parameters.
Returns a ReflectionType object if a return type is
specified, NULL
otherwise.
Example #1 ReflectionFunctionAbstract::getReturnType() example
<?php
function to_int($param) : int {
return (int) $param;
}
$reflection1 = new ReflectionFunction('to_int');
echo $reflection1->getReturnType();
The above example will output:
int
Example #2 Usage on built-in functions
<?php
$reflection2 = new ReflectionFunction('array_merge');
var_dump($reflection2->getReturnType());
The above example will output:
null
This is because many internal functions do not have types specified for their parameters or return values. It is therefore best to avoid using this method on built-in functions.