<!DOCTYPE html PUBLIC
"-//W3C//DTD HTML 4.0 Transitional//EN">
<link rel=
"STYLESHEET" href=
"lib.css" type='text/css'
/>
<link rel=
"SHORTCUT ICON" href=
"../icons/pyfav.png" type=
"image/png" />
<link rel='start' href='../index.html' title='Python Documentation Index'
/>
<link rel=
"first" href=
"lib.html" title='Python Library Reference'
/>
<link rel='contents' href='contents.html'
title=
"Contents" />
<link rel='index' href='genindex.html' title='Index'
/>
<link rel='last' href='about.html' title='About this document...'
/>
<link rel='help' href='about.html' title='About this document...'
/>
<link rel=
"next" href=
"bltin-code-objects.html" />
<link rel=
"prev" href=
"typesfunctions.html" />
<link rel=
"parent" href=
"typesother.html" />
<link rel=
"next" href=
"bltin-code-objects.html" />
<meta name='aesop' content='information'
/>
<title>2.3.10.4 Methods
</title>
<div id='top-navigation-panel' xml:id='top-navigation-panel'
>
<table align=
"center" width=
"100%" cellpadding=
"0" cellspacing=
"2">
<td class='online-navigation'
><a rel=
"prev" title=
"2.3.10.3 Functions"
href=
"typesfunctions.html"><img src='../icons/previous.png'
border='
0' height='
32' alt='Previous Page' width='
32'
/></A></td>
<td class='online-navigation'
><a rel=
"parent" title=
"2.3.10 Other Built-in Types"
href=
"typesother.html"><img src='../icons/up.png'
border='
0' height='
32' alt='Up One Level' width='
32'
/></A></td>
<td class='online-navigation'
><a rel=
"next" title=
"2.3.10.5 Code Objects"
href=
"bltin-code-objects.html"><img src='../icons/next.png'
border='
0' height='
32' alt='Next Page' width='
32'
/></A></td>
<td align=
"center" width=
"100%">Python Library Reference
</td>
<td class='online-navigation'
><a rel=
"contents" title=
"Table of Contents"
href=
"contents.html"><img src='../icons/contents.png'
border='
0' height='
32' alt='Contents' width='
32'
/></A></td>
<td class='online-navigation'
><a href=
"modindex.html" title=
"Module Index"><img src='../icons/modules.png'
border='
0' height='
32' alt='Module Index' width='
32'
/></a></td>
<td class='online-navigation'
><a rel=
"index" title=
"Index"
href=
"genindex.html"><img src='../icons/index.png'
border='
0' height='
32' alt='Index' width='
32'
/></A></td>
<div class='online-navigation'
>
<b class=
"navlabel">Previous:
</b>
<a class=
"sectref" rel=
"prev" href=
"typesfunctions.html">2.3.10.3 Functions
</A>
<b class=
"navlabel">Up:
</b>
<a class=
"sectref" rel=
"parent" href=
"typesother.html">2.3.10 Other Built-in Types
</A>
<b class=
"navlabel">Next:
</b>
<a class=
"sectref" rel=
"next" href=
"bltin-code-objects.html">2.3.10.5 Code Objects
</A>
<!--End of Navigation Panel-->
<H3><A NAME=
"SECTION0043104000000000000000"></A><A NAME=
"typesmethods"></A>
<a id='l2h-
260' xml:id='l2h-
260'
></a>
Methods are functions that are called using the attribute notation.
There are two flavors: built-in methods (such as
<tt class=
"method">append()
</tt> on
lists) and class instance methods. Built-in methods are described
with the types that support them.
The implementation adds two special read-only attributes to class
instance methods:
<code><var>m
</var>.im_self
</code> is the object on which the
method operates, and
<code><var>m
</var>.im_func
</code> is the function
implementing the method. Calling
<code><var>m
</var>(
<var>arg-
1</var>,
<var>arg-
2</var>, ...,
<var>arg-n
</var>)
</code> is completely equivalent to
calling
<code><var>m
</var>.im_func(
<var>m
</var>.im_self,
<var>arg-
1</var>,
<var>arg-
2</var>, ...,
<var>arg-n
</var>)
</code>.
Class instance methods are either
<em>bound
</em> or
<em>unbound
</em>,
referring to whether the method was accessed through an instance or a
class, respectively. When a method is unbound, its
<code>im_self
</code>
attribute will be
<code>None
</code> and if called, an explicit
<code>self
</code>
object must be passed as the first argument. In this case,
<code>self
</code> must be an instance of the unbound method's class (or a
subclass of that class), otherwise a
<code>TypeError
</code> is raised.
Like function objects, methods objects support getting
arbitrary attributes. However, since method attributes are actually
stored on the underlying function object (
<code>meth.im_func
</code>),
setting method attributes on either bound or unbound methods is
disallowed. Attempting to set a method attribute results in a
<code>TypeError
</code> being raised. In order to set a method attribute,
you need to explicitly set it on the underlying function object:
<div class=
"verbatim"><pre>
c.method.im_func.whoami = 'my name is c'
See the
<em class=
"citetitle"><a
title=
"Python Reference Manual"
>Python Reference Manual
</a></em> for more
<div class='online-navigation'
>
<table align=
"center" width=
"100%" cellpadding=
"0" cellspacing=
"2">
<td class='online-navigation'
><a rel=
"prev" title=
"2.3.10.3 Functions"
href=
"typesfunctions.html"><img src='../icons/previous.png'
border='
0' height='
32' alt='Previous Page' width='
32'
/></A></td>
<td class='online-navigation'
><a rel=
"parent" title=
"2.3.10 Other Built-in Types"
href=
"typesother.html"><img src='../icons/up.png'
border='
0' height='
32' alt='Up One Level' width='
32'
/></A></td>
<td class='online-navigation'
><a rel=
"next" title=
"2.3.10.5 Code Objects"
href=
"bltin-code-objects.html"><img src='../icons/next.png'
border='
0' height='
32' alt='Next Page' width='
32'
/></A></td>
<td align=
"center" width=
"100%">Python Library Reference
</td>
<td class='online-navigation'
><a rel=
"contents" title=
"Table of Contents"
href=
"contents.html"><img src='../icons/contents.png'
border='
0' height='
32' alt='Contents' width='
32'
/></A></td>
<td class='online-navigation'
><a href=
"modindex.html" title=
"Module Index"><img src='../icons/modules.png'
border='
0' height='
32' alt='Module Index' width='
32'
/></a></td>
<td class='online-navigation'
><a rel=
"index" title=
"Index"
href=
"genindex.html"><img src='../icons/index.png'
border='
0' height='
32' alt='Index' width='
32'
/></A></td>
<div class='online-navigation'
>
<b class=
"navlabel">Previous:
</b>
<a class=
"sectref" rel=
"prev" href=
"typesfunctions.html">2.3.10.3 Functions
</A>
<b class=
"navlabel">Up:
</b>
<a class=
"sectref" rel=
"parent" href=
"typesother.html">2.3.10 Other Built-in Types
</A>
<b class=
"navlabel">Next:
</b>
<a class=
"sectref" rel=
"next" href=
"bltin-code-objects.html">2.3.10.5 Code Objects
</A>
<span class=
"release-info">Release
2.4.2, documentation updated on
28 September
2005.
</span>
<!--End of Navigation Panel-->
See
<i><a href=
"about.html">About this document...
</a></i> for information on suggesting changes.