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List:       php-doc-cvs
Subject:    [DOC-CVS] =?utf-8?q?svn:_/phpdoc/en/trunk/language/_functions.xml?=
From:       Pasindu_De_Silva <pasindu () php ! net>
Date:       2015-07-18 12:06:20
Message-ID: svn-pasindu-1437221180-337187-1241741405 () svn ! php ! net
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pasindu                                  Sat, 18 Jul 2015 12:06:20 +0000

Revision: http://svn.php.net/viewvc?view=revision&revision=337187

Log:
Added initial return type declarations

Changed paths:
    U   phpdoc/en/trunk/language/functions.xml

Modified: phpdoc/en/trunk/language/functions.xml
===================================================================
--- phpdoc/en/trunk/language/functions.xml	2015-07-18 07:50:57 UTC (rev 337186)
+++ phpdoc/en/trunk/language/functions.xml	2015-07-18 12:06:20 UTC (rev 337187)
@@ -774,6 +774,8 @@
      returned.
     </para>
    </note>
+   <sect2>
+    <title>Use of return</title>
    <para>
     <example>
      <title>Use of <function>return</function></title>
@@ -837,6 +839,123 @@
     For more information on references, please check out <link
     linkend="language.references">References Explained</link>.
    </simpara>
+  </sect2>
+  <sect2>
+     <title>Return Type Declarations</title>
+     <para>
+       PHP 7 Introduces Return type delaration where function can be forced to \
return +       type that is defined. This done by setting
+       <link linkend="control-structures.declare">declare(strict_types=1)</link>, if \
declare strict_type directive +       is set to 0 or not set functions are weakly \
type checked.  The directive will have affect on all functions +       delcared in \
the file and not functions either included by this file or files that includes this \
file, are +       affected. The place where the function is called from is \
irrelavent. +       Declarable types are Classes, Interfaces, Array, Int, Float, \
String and Bool. +     </para>
+  <para>
+    <example>
+     <title>Affect of strict_types directive </title>
+     <programlisting role="php">
+<![CDATA[
+<?php
+declare(strict_types=1); // file1.php
+
+// file 1 - strictly type checked
+// file 2 - weakly type checked
+
+include "file2.php";
+
+var_dump(a()); // works correctly
+var_dump(b()); // fatal TypeError
+
+
+function b() : int{
+   return "1";
+}
+?>
+
+
+<?php
+// file2.php
+function a(): int{
+   return "1";
+}
+
+?>
+]]>
+     </programlisting>
+    </example>
+  </para>
+  <para>
+    <example>
+     <title>More Return types</title>
+     <para>
+      The function signature must match of the parent, if the parent has not been \
declared the +      return type the child can declare a type.
+     </para>
+     <programlisting role="php">
+<![CDATA[
+<?php
+declare(strict_types=1);
+
+interface Numbers{
+  abstract public function one() : int ;
+  abstract public function two();         // no return type defined
+}
+
+class NumClass implements Numbers
+{
+  public function one()  : int {  // return type same as abstract
+    return 0;
+  }
+
+  public function two()  {  // return type defined due lack of return type
+    return 2;               // in parent abstract function
+  }
+}
+
+class display extends NumClass
+{
+  public function one() : int // return type same as parent
+  {
+    return 1;
+  }
+
+  public function two() : int // return type same as parent
+  {
+    return 2;
+  }
+}
+
+$dis = new display();
+var_dump($dis->one());
+var_dump($dis->two());
+
+?>
+]]>
+     </programlisting>
+    </example>
+ </para>
+ <para>
+    <example>
+     <title>Return a class;</title>
+     <programlisting role="php">
+<![CDATA[
+<?php
+declare(strict_types=1);
+
+interface A {
+    static function make();
+}
+class B implements A {
+    static function make(): B { //valid
+        return new B();
+    }
+}
+]]>
+     </programlisting>
+    </example>
+  </para>
+   </sect2>
   </sect1>

   <sect1 xml:id="functions.variable-functions">
@@ -1259,4 +1378,4 @@
 vim600: syn=xml fen fdm=syntax fdl=2 si
 vim: et tw=78 syn=sgml
 vi: ts=1 sw=1
--->
+-->
\ No newline at end of file



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