One of the beautifull feature of programming languages came out in PHP 7 that now we also can have function return type in PHP like we have in other languages like Java, C, C# etc..
So PHP 7 adds support for return type declarations.
Now we can force a function to return a specific type of data.
In PHP 7 we have following function return types:
int : Integer data type.
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<?php
function testInt() : int{
return 5;
}
var_dump(testInt());
?>
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float : Float data type.
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<?php
function testFloat() : float{
return 5.2;
}
var_dump(testFloat());
?>
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array : Array data type.
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<?php
function testArray(): array {
return [];
}
var_dump(testArray());
?>
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bool : Boolean data type.
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<?php
function testBoolean() : bool{
return 1;
}
var_dump(testBoolean());
?>
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string: String data type.
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<?php
function testString() : string{
return 'coding 4 developers';
}
var_dump(testString());
?>
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Class/Interface name : Name of the class.
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<?php
class class1{}
class class2{
public function __construct() {
}
function get_class_1_object() :class1{
return new class1;
}
}
$x = new class2;
$y = $x->get_class_1_object();
var_dump($y);
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<?php
interface A {
static function make(): A;
}
class B implements A {
static function make(): A {
return new B();
}
}
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self : Instance of the same class. This can only be used if function is created under any class.
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<?php
class test1{
}
class test2{
function testSelf() : ? self{
return new test2();
}
}
$obj = new test2();
var_dump($obj->testSelf());
?>
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callable : Valid PHP callable.
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<?php
class test{
static function testCallable(){
return 1;
}
}
function test():callable{
$x = new test;
return array($x , 'testCallable' );
return 1;
}
var_dump(is_callable(test()));
?>
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