Checks if the function has a specified return type

# ReflectionFunctionAbstract::hasReturnType

(PHP 7)

ReflectionFunctionAbstract::hasReturnType — Checks if the function has a specified return type

### 説明

public ReflectionFunctionAbstract::hasReturnType ( void ) : bool

Checks whether the reflected function has a return type specified.

### パラメータ

この関数にはパラメータはありません。

### 返り値

Returns `TRUE` if the function is a specified return type, otherwise `FALSE`.

### 例

例1 ReflectionFunctionAbstract::hasReturnType() example

`<?php
function to_int($param) : int {
return (int) $param;
}
$reflection1 = new ReflectionFunction('to_int');
var_dump($reflection1->hasReturnType());`

上の例の出力は以下となります。

    bool(true)

例2 Usage on built-in functions

`<?php
$reflection2 = new ReflectionFunction('array_merge');
var_dump($reflection2->hasReturnType());`

上の例の出力は以下となります。

    bool(false)

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.

### 参考

- ReflectionFunctionAbstract::getReturnType() - Gets the specified return type of a function