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<H3>
<BR>
2.1.4.1 Bit-string Operations on Integer Types
</H3>
<P>
Plain and long integer types support additional operations that make
sense only for bit-strings. Negative numbers are treated as their 2's
complement value (for long integers, this assumes a sufficiently large
number of bits that no overflow occurs during the operation).
<P>
The priorities of the binary bit-wise operations are all lower than
the numeric operations and higher than the comparisons; the unary
operation "<tt class="samp">~</tt>" has the same priority as the other unary numeric
operations ("<tt class="samp">+</tt>" and "<tt class="samp">-</tt>").
<P>
This table lists the bit-string operations sorted in ascending
priority (operations in the same box have the same priority):
<P>
<table border align="center" style="border-collapse: collapse">
<thead>
<tr>
<th align="center"><b>Operation</b> </th>
<th align="left"><b>Result</b> </th>
<th align="center"><b>Notes</b> </th>
</thead>
<tbody valign='baseline'>
<tr><td align="center" valign="baseline"><code><var>x</var> | <var>y</var></code></td>
<td align="left">bitwise <i class="dfn">or</i> of <var>x</var> and <var>y</var></td>
<td align="center"> </td>
<tr><td align="center" valign="baseline"><code><var>x</var> ^ <var>y</var></code></td>
<td align="left">bitwise <i class="dfn">exclusive or</i> of <var>x</var> and <var>y</var></td>
<td align="center"> </td>
<tr><td align="center" valign="baseline"><code><var>x</var> & <var>y</var></code></td>
<td align="left">bitwise <i class="dfn">and</i> of <var>x</var> and <var>y</var></td>
<td align="center"> </td>
<tr><td align="center" valign="baseline"><code><var>x</var> « <var>n</var></code></td>
<td align="left"><var>x</var> shifted left by <var>n</var> bits</td>
<td align="center">(1), (2)</td>
<tr><td align="center" valign="baseline"><code><var>x</var> » <var>n</var></code></td>
<td align="left"><var>x</var> shifted right by <var>n</var> bits</td>
<td align="center">(1), (3)</td>
<tr><td align="center" valign="baseline"><code>~<var>x</var></code></td>
<td align="left">the bits of <var>x</var> inverted</td>
<td align="center"> </td></tbody>
</table>
<P>
Notes:
<DL>
<DT><STRONG>(1)</STRONG></DT>
<DD>Negative shift counts are illegal and cause a
<tt class="exception">ValueError</tt> to be raised.
</DD>
<DT><STRONG>(2)</STRONG></DT>
<DD>A left shift by <var>n</var> bits is equivalent to
multiplication by <code>pow(2, <var>n</var>)</code> without overflow check.
</DD>
<DT><STRONG>(3)</STRONG></DT>
<DD>A right shift by <var>n</var> bits is equivalent to
division by <code>pow(2, <var>n</var>)</code> without overflow check.
</DD>
</DL>
<P>
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