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<title>6.6 The print statement </title>
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<H1><A NAME="SECTION008600000000000000000"></A><A NAME="print"></A>
<BR>
6.6 The <tt class="keyword">print</tt> statement
</H1>
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<P>
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    <td><a id='tok-print_stmt' xml:id='tok-print_stmt'>print_stmt</a></td>
    <td>::=</td>
    <td>"print" ( <big>[</big><a class='grammartoken' href="Booleans.html#tok-expression">expression</a> ("," <a class='grammartoken' href="Booleans.html#tok-expression">expression</a>)* <big>[</big>","<big>]</big><big>]</big></td></tr>
  <tr>
    <td></td>
    <td></td>
    <td><code>| "&gt;<code>&gt;</code>" <a class='grammartoken' href="Booleans.html#tok-expression">expression</a>
                  <big>[</big>("," <a class='grammartoken' href="Booleans.html#tok-expression">expression</a>)+ <big>[</big>","<big>]</big><big>]</big> )</code></td></tr>
</table>
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<a class="grammar-footer"
  href="grammar.txt" type="text/plain"
  >Download entire grammar as text.</a>
</dd></dl>

<P>
<tt class="keyword">print</tt> evaluates each expression in turn and writes the
resulting object to standard output (see below).  If an object is not
a string, it is first converted to a string using the rules for string
conversions.  The (resulting or original) string is then written.  A
space is written before each object is (converted and) written, unless
the output system believes it is positioned at the beginning of a
line.  This is the case (1) when no characters have yet been written
to standard output, (2) when the last character written to standard
output is "<tt class="character">&#92;n</tt>", or (3) when the last write operation on
standard output was not a <tt class="keyword">print</tt> statement.  (In some cases
it may be functional to write an empty string to standard output for
this reason.)  <span class="note"><b class="label">Note:</b>
Objects which act like file objects but which are
not the built-in file objects often do not properly emulate this
aspect of the file object's behavior, so it is best not to rely on
this.</span>
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<a id='l2h-496' xml:id='l2h-496'></a>
<P>
A "<tt class="character">&#92;n</tt>" character is written at the end, unless the
<tt class="keyword">print</tt> statement ends with a comma.  This is the only action
if the statement contains just the keyword <tt class="keyword">print</tt>.
<a id='l2h-497' xml:id='l2h-497'></a><a id='l2h-498' xml:id='l2h-498'></a>
<P>
Standard output is defined as the file object named <code>stdout</code>
in the built-in module <tt class="module">sys</tt>.  If no such object exists, or if
it does not have a <tt class="method">write()</tt> method, a <tt class="exception">RuntimeError</tt>
exception is raised.
<a id='l2h-499' xml:id='l2h-499'></a><a id='l2h-504' xml:id='l2h-504'></a>
<a id='l2h-501' xml:id='l2h-501'></a><a id='l2h-502' xml:id='l2h-502'></a>
<P>
<tt class="keyword">print</tt> also has an extended<a id='l2h-505' xml:id='l2h-505'></a>
form, defined by the second portion of the syntax described above.
This form is sometimes referred to as ``<tt class="keyword">print</tt> chevron.''
In this form, the first expression after the <code>&gt;</code><code>&gt;</code> must
evaluate to a ``file-like'' object, specifically an object that has a
<tt class="method">write()</tt> method as described above.  With this extended form,
the subsequent expressions are printed to this file object.  If the
first expression evaluates to <code>None</code>, then <code>sys.stdout</code> is
used as the file for output.

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<span class="release-info">Release 2.4.2, documentation updated on 28 September 2005.</span>
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