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<H2><A NAME="SECTION007270000000000000000"></A><A NAME="string-conversions"></A>
<BR>
5.2.7 String conversions
</H2>
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<P>
A string conversion is an expression list enclosed in reverse (a.k.a.
backward) quotes:
<P>
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<td><a id='tok-string_conversion' xml:id='tok-string_conversion'>string_conversion</a></td>
<td>::=</td>
<td>"`" <a class='grammartoken' href="exprlists.html#tok-expression_list">expression_list</a> "`"</td></tr>
</table>
</div>
<a class="grammar-footer"
href="grammar.txt" type="text/plain"
>Download entire grammar as text.</a>
</dd></dl>
<P>
A string conversion evaluates the contained expression list and
converts the resulting object into a string according to rules
specific to its type.
<P>
If the object is a string, a number, <code>None</code>, or a tuple, list or
dictionary containing only objects whose type is one of these, the
resulting string is a valid Python expression which can be passed to
the built-in function <tt class="function">eval()</tt> to yield an expression with the
same value (or an approximation, if floating point numbers are
involved).
<P>
(In particular, converting a string adds quotes around it and converts
``funny'' characters to escape sequences that are safe to print.)
<P>
Recursive objects (for example, lists or dictionaries that contain a
reference to themselves, directly or indirectly) use "<tt class="samp">...</tt>" to
indicate a recursive reference, and the result cannot be passed to
<tt class="function">eval()</tt> to get an equal value (<tt class="exception">SyntaxError</tt> will
be raised instead).
<a id='l2h-359' xml:id='l2h-359'></a>
<P>
The built-in function <tt class="function">repr()</tt> performs exactly the same
conversion in its argument as enclosing it in parentheses and reverse
quotes does. The built-in function <tt class="function">str()</tt> performs a
similar but more user-friendly conversion.
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<span class="release-info">Release 2.4.3, documentation updated on 29 March 2006.</span>
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