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<H3><A NAME="SECTION004341000000000000000"></A><A NAME="bitstring-ops"></A>
<BR>
2.3.4.1 Bit-string Operations on Integer Types 
</H3>
<A NAME="Bit-string_Operations"></A>
<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>
<div class="center"><table class="realtable">
  <thead>
    <tr>
      <th class="center">Operation</th>
      <th class="left"  >Result</th>
      <th class="center">Notes</th>
      </tr>
    </thead>
  <tbody>
    <tr><td class="center" valign="baseline"><code><var>x</var> | <var>y</var></code></td>
        <td class="left"  >bitwise <i class="dfn">or</i> of <var>x</var> and <var>y</var></td>
        <td class="center"></td></tr>
    <tr><td class="center" valign="baseline"><code><var>x</var> ^ <var>y</var></code></td>
        <td class="left"  >bitwise <i class="dfn">exclusive or</i> of <var>x</var> and <var>y</var></td>
        <td class="center"></td></tr>
    <tr><td class="center" valign="baseline"><code><var>x</var> &amp; <var>y</var></code></td>
        <td class="left"  >bitwise <i class="dfn">and</i> of <var>x</var> and <var>y</var></td>
        <td class="center"></td></tr>
    <tr><td class="center" valign="baseline"><code><var>x</var> &lt;&lt; <var>n</var></code></td>
        <td class="left"  ><var>x</var> shifted left by <var>n</var> bits</td>
        <td class="center">(1), (2)</td></tr>
    <tr><td class="center" valign="baseline"><code><var>x</var> &gt;&gt; <var>n</var></code></td>
        <td class="left"  ><var>x</var> shifted right by <var>n</var> bits</td>
        <td class="center">(1), (3)</td></tr>
  
    <tr><td class="center" valign="baseline"><code>~<var>x</var></code></td>
        <td class="left"  >the bits of <var>x</var> inverted</td>
        <td class="center"></td></tr></tbody>
</table></div>
<a id='l2h-148' xml:id='l2h-148'></a><a id='l2h-149' xml:id='l2h-149'></a><a id='l2h-150' xml:id='l2h-150'></a><a id='l2h-151' xml:id='l2h-151'></a>
<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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	53
	54	<H3><A NAME="SECTION004341000000000000000"></A><A NAME="bitstring-ops"></A>
	55	<BR>
	56	2.3.4.1 Bit-string Operations on Integer Types
	57	</H3>
	58	<A NAME="Bit-string_Operations"></A>
	59	<P>
	60	Plain and long integer types support additional operations that make
	61	sense only for bit-strings. Negative numbers are treated as their 2's
	62	complement value (for long integers, this assumes a sufficiently large
	63	number of bits that no overflow occurs during the operation).
	64
65	<P>
66	The priorities of the binary bit-wise operations are all lower than
67	the numeric operations and higher than the comparisons; the unary
68	operation "<tt class="samp">~</tt>" has the same priority as the other unary numeric
69	operations ("<tt class="samp">+</tt>" and "<tt class="samp">-</tt>").
70
71	<P>
72	This table lists the bit-string operations sorted in ascending
73	priority (operations in the same box have the same priority):
74
75	<P>
76	<div class="center"><table class="realtable">
77	<thead>
78	<tr>
79	<th class="center">Operation</th>
80	<th class="left" >Result</th>
81	<th class="center">Notes</th>
82	</tr>
83	</thead>
84	<tbody>
85	<tr><td class="center" valign="baseline"><code><var>x</var> \| <var>y</var></code></td>
86	<td class="left" >bitwise <i class="dfn">or</i> of <var>x</var> and <var>y</var></td>
87	<td class="center"></td></tr>
88	<tr><td class="center" valign="baseline"><code><var>x</var> ^ <var>y</var></code></td>
89	<td class="left" >bitwise <i class="dfn">exclusive or</i> of <var>x</var> and <var>y</var></td>
90	<td class="center"></td></tr>
91	<tr><td class="center" valign="baseline"><code><var>x</var> & <var>y</var></code></td>
92	<td class="left" >bitwise <i class="dfn">and</i> of <var>x</var> and <var>y</var></td>
93	<td class="center"></td></tr>
94	<tr><td class="center" valign="baseline"><code><var>x</var> << <var>n</var></code></td>
95	<td class="left" ><var>x</var> shifted left by <var>n</var> bits</td>
96	<td class="center">(1), (2)</td></tr>
97	<tr><td class="center" valign="baseline"><code><var>x</var> >> <var>n</var></code></td>
98	<td class="left" ><var>x</var> shifted right by <var>n</var> bits</td>
99	<td class="center">(1), (3)</td></tr>
100
101	<tr><td class="center" valign="baseline"><code>~<var>x</var></code></td>
102	<td class="left" >the bits of <var>x</var> inverted</td>
103	<td class="center"></td></tr></tbody>
104	</table></div>
105	<a id='l2h-148' xml:id='l2h-148'></a><a id='l2h-149' xml:id='l2h-149'></a><a id='l2h-150' xml:id='l2h-150'></a><a id='l2h-151' xml:id='l2h-151'></a>
106	<P>
107	Notes:
108	<DL>
109	<DT><STRONG>(1)</STRONG></DT>
110	<DD>Negative shift counts are illegal and cause a
111	<tt class="exception">ValueError</tt> to be raised.
112	</DD>
113	<DT><STRONG>(2)</STRONG></DT>
114	<DD>A left shift by <var>n</var> bits is equivalent to
115	multiplication by <code>pow(2, <var>n</var>)</code> without overflow check.
116	</DD>
117	<DT><STRONG>(3)</STRONG></DT>
118	<DD>A right shift by <var>n</var> bits is equivalent to
119	division by <code>pow(2, <var>n</var>)</code> without overflow check.
120	</DD>
121	</DL>
122
123	<P>
124
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