PHP 7.1.0 Released

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User Contributed Notes 5 notes

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133
Anonymous
5 years ago
The keyword 'use' has two different applications, but the reserved word table links to here.

It can apply to namespace constucts:

file1:
<?php namespace foo;
  class
Cat {
    static function
says() {echo 'meoow';}  } ?>

file2:
<?php namespace bar;
  class
Dog {
    static function
says() {echo 'ruff';}  } ?>

file3:
<?php namespace animate;
  class
Animal {
    static function
breathes() {echo 'air';}  } ?>

file4:
<?php namespace fub;
  include
'file1.php';
  include
'file2.php';
  include
'file3.php';
  use
foo as feline;
  use
bar as canine;
  use
animate;
  echo \
feline\Cat::says(), "<br />\n";
  echo \
canine\Dog::says(), "<br />\n";
  echo \
animate\Animal::breathes(), "<br />\n"?>

Note that
felineCat::says()
should be
\feline\Cat::says()
(and similar for the others)
but this comment form deletes the backslash (why???)

The 'use' keyword also applies to closure constructs:

<?php function getTotal($products_costs, $tax)
    {
       
$total = 0.00;
       
       
$callback =
            function (
$pricePerItem) use ($tax, &$total)
            {
               
               
$total += $pricePerItem * ($tax + 1.0);
            };
       
       
array_walk($products_costs, $callback);
        return
round($total, 2);
    }
?>
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15
varuninorbit at yahoo dot co dot in
11 months ago
here is a simple example to use namespace

<?php

namespace app\a{
    class
one{
       public static function
_1(){
        echo
'a one _1<br>';
       }
    }
}

namespace
app\b{
    class
one{
        public static function
_2(){
            echo
'b one _2<br>';
        }
    }
}

namespace
app{

    echo
a\one::_1();
    echo
b\one::_2();
    echo
a\two::_1();
}

namespace
app\a{
    class
two{
       public static function
_1(){
        echo
'a two _1<br>';
       }
    }
}

prints
a one _1
b one _2
a two _1
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6
Anonymous
6 months ago
Tested on PHP 7.0.5, Windows
The line "use animate;" equals the line "use animate as animate;"
but the "use other\animate;" equals "use other\animate as animate;"

file1:
<?php namespace foo;
  class
Cat {
    static function
says() {echo 'meoow';}  } ?>

file2:
<?php namespace bar;
  class
Dog {
    static function
says() {echo 'ruff';}  } ?>

file3:
<?php namespace other\animate;
  class
Animal {
    static function
breathes() {echo 'air';}  } ?>

file4:
<?php namespace fub;
  include
'file1.php';
  include
'file2.php';
  include
'file3.php';
  use
foo as feline;
  use
bar as canine;
  use
other\animate;       //use other\animate as animate;
 
echo feline\Cat::says(), "<br />\n";
  echo
canine\Dog::says(), "<br />\n";
  echo \
animate\Animal::breathes(), "<br />\n"?>
up
13
davidkennedy85 at gmail dot com
1 year ago
In addition to using namespaces and closures, the use keyword has another new meaning as of PHP 5.4 - using traits:

<?php
trait Hello {
    public function
sayHello() {
        echo
'Hello ';
    }
}

trait
World {
    public function
sayWorld() {
        echo
'World';
    }
}

class
MyHelloWorld {
    use
Hello, World;
    public function
sayExclamationMark() {
        echo
'!';
    }
}

$o = new MyHelloWorld();
$o->sayHello();
$o->sayWorld();
$o->sayExclamationMark();
?>

More info here: http://php.net/manual/en/language.oop5.traits.php
up
-23
Ronald W
1 year ago
<?php
// multiple namespaces in a single file:

namespace foo{
  class
Cat {
    static function
says() {echo 'meoow';}  }
}

namespace
bar{
  class
Dog {
    static function
says() {echo 'ruff';}  } 
  class
Cat {
    static function
says() {echo 'meowi';}  }
  class
Mouse {     //nonstatic function
   
function says() {echo 'Come and get me ;)';}  }
}

namespace
animate{
  class
Animal {
    static function
breathes() {echo 'air';}  }
}

namespace{       
// No Namespace: global code
 
use foo as feline;
  use
bar as canine;
  use
bar\Mouse as MouseOnly;
  use
animate;
  echo
animate\Animal::breathes(), "<br />\n"
  echo
feline\Cat::says(), "<br />\n"; //not starting with a slash!
 
echo canine\Cat::says(), "<br />\n";
  echo
canine\Dog::says(), "<br />\n";
 
//any of the three following lines work:
  // $micky=new bar\Mouse();
  // $micky=new canine\Mouse();
 
$micky=new test();
  echo
$micky->says();
}
?>
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