sean Sat Jan 29 09:43:56 2005 EDT
Modified files:
/phpdoc/en/language/oop5 basic.xml
Log:
document seemingly-odd $this behaviour
http://cvs.php.net/diff.php/phpdoc/en/language/oop5/basic.xml?r1=1.12&r2=1.13&ty=u
Index: phpdoc/en/language/oop5/basic.xml
diff -u phpdoc/en/language/oop5/basic.xml:1.12
phpdoc/en/language/oop5/basic.xml:1.13
--- phpdoc/en/language/oop5/basic.xml:1.12 Mon Jan 24 03:23:35 2005
+++ phpdoc/en/language/oop5/basic.xml Sat Jan 29 09:43:56 2005
@@ -1,5 +1,5 @@
<?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.12 $ -->
+<!-- $Revision: 1.13 $ -->
<sect1 id="language.oop5.basic">
<title>The Basics</title>
@@ -10,11 +10,58 @@
Every class definition begins with the keyword class, followed by a class
name, which can be any name that isn't a <link
linkend="reserved">reserved</link>
word in PHP. Followed by a pair of curly braces, of
- which contains the definition of the classes members and methods. Within
- each method, except for <link linkend="language.oop5.static">static</link>
- methods, a pseudo variable <varname>$this</varname> is available.
- <varname>$this</varname> is a reference to the same instance that
- called the method.
+ which contains the definition of the classes members and methods. A
+ pseudo-variable, <varname>$this</varname> is available when a method is
+ called from within an object context. <varname>$this</varname> is a
+ reference to the calling object (usually the object to which the method
+ belongs, but can be another object, if the method is called
+ <link linkend="language.oop5.static">statically</link> from the context
+ of a secondary object). This is illustrated in the following example:
+ <informalexample>
+ <programlisting role="php">
+<![CDATA[
+<?php
+class A
+{
+ function foo()
+ {
+ if (isset($this)) {
+ echo '$this is defined (';
+ echo get_class($this);
+ echo ")\n";
+ } else {
+ echo "\$this is not defined.\n";
+ }
+ }
+}
+
+class B
+{
+ function bar()
+ {
+ A::foo();
+ }
+}
+
+$a = new A();
+$a->foo();
+A::foo();
+$b = new B();
+$b->bar();
+B::bar();
+?>
+]]>
+ </programlisting>
+ &example.outputs;
+ <screen>
+<![CDATA[
+$this is defined (a)
+$this is not defined.
+$this is defined (b)
+$this is not defined.
+]]>
+ </screen>
+ </informalexample>
</para>
<example>
<title>Simple Class definition</title>
