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Update Boost.Integer meta-programming classes to work with intmax_t where possible - ie to be 64-bit clean.
Added quickbook based docs - updated as necessary. Removed old html docs. [SVN r57926]
This commit is contained in:
John Maddock
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doc/html/boost_integer/mask.html
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doc/html/boost_integer/mask.html
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<html>
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<head>
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<title>Integer Masks</title>
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<div class="titlepage"><div><div><h2 class="title" style="clear: both">
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<a name="boost_integer.mask"></a><a class="link" href="mask.html" title="Integer Masks"> Integer Masks</a>
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</h2></div></div></div>
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<div class="toc"><dl>
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<dt><span class="section"><a href="mask.html#boost_integer.mask.overview">Overview</a></span></dt>
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<dt><span class="section"><a href="mask.html#boost_integer.mask.synopsis">Synopsis</a></span></dt>
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<dt><span class="section"><a href="mask.html#boost_integer.mask.single_bit_mask_class_template">Single
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Bit-Mask Class Template</a></span></dt>
|
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<dt><span class="section"><a href="mask.html#boost_integer.mask.group_bit_mask_class_template">Group
|
||||
Bit-Mask Class Template</a></span></dt>
|
||||
<dt><span class="section"><a href="mask.html#boost_integer.mask.implementation_notes">Implementation
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||||
Notes</a></span></dt>
|
||||
<dt><span class="section"><a href="mask.html#boost_integer.mask.example">Example</a></span></dt>
|
||||
<dt><span class="section"><a href="mask.html#boost_integer.mask.demonstration_program">Demonstration
|
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Program</a></span></dt>
|
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<dt><span class="section"><a href="mask.html#boost_integer.mask.rationale">Rationale</a></span></dt>
|
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<dt><span class="section"><a href="mask.html#boost_integer.mask.credits">Credits</a></span></dt>
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</dl></div>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h3 class="title">
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<a name="boost_integer.mask.overview"></a><a class="link" href="mask.html#boost_integer.mask.overview" title="Overview">Overview</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
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The class templates in <a href="../../../../../boost/integer/integer_mask.hpp" target="_top"><boost/integer/integer_mask.hpp></a>
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||||
provide bit masks for a certain bit position or a contiguous-bit pack of
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a certain size. The types of the masking constants come from the <a class="link" href="integer.html" title="Integer Type Selection">integer
|
||||
type selection templates</a> header.
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||||
</p>
|
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</div>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h3 class="title">
|
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<a name="boost_integer.mask.synopsis"></a><a class="link" href="mask.html#boost_integer.mask.synopsis" title="Synopsis">Synopsis</a>
|
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</h3></div></div></div>
|
||||
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">cstddef</span><span class="special">></span> <span class="comment">// for std::size_t
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</span>
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<span class="keyword">namespace</span> <span class="identifier">boost</span>
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<span class="special">{</span>
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|
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<span class="keyword">template</span> <span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">Bit</span><span class="special">></span>
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<span class="keyword">struct</span> <span class="identifier">high_bit_mask_t</span>
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<span class="special">{</span>
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<span class="keyword">typedef</span> <span class="emphasis"><em>implementation-defined-type</em></span> <span class="identifier">least</span><span class="special">;</span>
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<span class="keyword">typedef</span> <span class="emphasis"><em>implementation-defined-type</em></span> <span class="identifier">fast</span><span class="special">;</span>
|
||||
|
||||
<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">least</span> <span class="identifier">high_bit</span> <span class="special">=</span> <span class="emphasis"><em>implementation-defined</em></span><span class="special">;</span>
|
||||
<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">fast</span> <span class="identifier">high_bit_fast</span> <span class="special">=</span> <span class="emphasis"><em>implementation-defined</em></span><span class="special">;</span>
|
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|
||||
<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bit_position</span> <span class="special">=</span> <span class="identifier">Bit</span><span class="special">;</span>
|
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<span class="special">};</span>
|
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|
||||
<span class="keyword">template</span> <span class="special"><</span><span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">Bits</span><span class="special">></span>
|
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<span class="keyword">struct</span> <span class="identifier">low_bits_mask_t</span>
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<span class="special">{</span>
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<span class="keyword">typedef</span> <span class="emphasis"><em>implementation-defined-type</em></span> <span class="identifier">least</span><span class="special">;</span>
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<span class="keyword">typedef</span> <span class="emphasis"><em>implementation-defined-type</em></span> <span class="identifier">fast</span><span class="special">;</span>
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<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">least</span> <span class="identifier">sig_bits</span> <span class="special">=</span> <span class="emphasis"><em>implementation-defined</em></span><span class="special">;</span>
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<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">fast</span> <span class="identifier">sig_bits_fast</span> <span class="special">=</span> <span class="emphasis"><em>implementation-defined</em></span><span class="special">;</span>
|
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|
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<span class="keyword">static</span> <span class="keyword">const</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span class="identifier">bit_count</span> <span class="special">=</span> <span class="identifier">Bits</span><span class="special">;</span>
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<span class="special">};</span>
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<span class="comment">// Specializations for low_bits_mask_t exist for certain bit counts.
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</span>
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<span class="special">}</span> <span class="comment">// namespace boost
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||||
</span></pre>
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</div>
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<div class="section" lang="en">
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<div class="titlepage"><div><div><h3 class="title">
|
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<a name="boost_integer.mask.single_bit_mask_class_template"></a><a class="link" href="mask.html#boost_integer.mask.single_bit_mask_class_template" title="Single Bit-Mask Class Template">Single
|
||||
Bit-Mask Class Template</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
||||
The <code class="literal">boost::high_bit_mask_t</code> class template provides constants
|
||||
for bit masks representing the bit at a certain position. The masks are equivalent
|
||||
to the value 2<sup>Bit</sup>, where <code class="literal">Bit</code> is the template parameter.
|
||||
The bit position must be a nonnegative number from zero to <span class="emphasis"><em>Max</em></span>,
|
||||
where Max is one less than the number of bits supported by the largest unsigned
|
||||
built-in integral type. The following table describes the members of an instantiation
|
||||
of <code class="literal">high_bit_mask_t</code>.
|
||||
</p>
|
||||
<div class="table">
|
||||
<a name="id674116"></a><p class="title"><b>Table<EFBFBD>2.<2E>Members of the `boost::high_bit_mask_t` Class Template</b></p>
|
||||
<div class="table-contents"><table class="table" summary="Members of the `boost::high_bit_mask_t` Class Template">
|
||||
<colgroup>
|
||||
<col>
|
||||
<col>
|
||||
</colgroup>
|
||||
<thead><tr>
|
||||
<th>
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||||
<p>
|
||||
Member
|
||||
</p>
|
||||
</th>
|
||||
<th>
|
||||
<p>
|
||||
Meaning
|
||||
</p>
|
||||
</th>
|
||||
</tr></thead>
|
||||
<tbody>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">least</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
The smallest unsigned built-in type that supports the given bit position.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">fast</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
The quick-to-manipulate analog of <code class="literal">least</code>.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">high_bit</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
A <code class="literal">least</code> constant of the desired bit-masking value.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">high_bit_fast</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
A <code class="literal">fast</code> analog of <code class="literal">high_bit</code>.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">bit_position</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
The value of the template parameter, in case its needed from a renamed
|
||||
instantiation of the class template.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table></div>
|
||||
</div>
|
||||
<br class="table-break">
|
||||
</div>
|
||||
<div class="section" lang="en">
|
||||
<div class="titlepage"><div><div><h3 class="title">
|
||||
<a name="boost_integer.mask.group_bit_mask_class_template"></a><a class="link" href="mask.html#boost_integer.mask.group_bit_mask_class_template" title="Group Bit-Mask Class Template">Group
|
||||
Bit-Mask Class Template</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
||||
The <code class="literal">boost::low_bits_mask_t</code> class template provides constants
|
||||
for bit masks representing the lowest bits of a certain amount. The masks
|
||||
are equivalent to the value (2<sup>Bits</sup> - 1), where <code class="literal">Bits</code> is
|
||||
the template parameter. The bit amount must be a nonnegative number from
|
||||
zero to <span class="emphasis"><em>Max</em></span>, where Max is the number of bits supported
|
||||
by the largest unsigned built-in integral type. The following table describes
|
||||
the members of an instantiation of <code class="literal">low_bits_mask_t</code>.
|
||||
</p>
|
||||
<div class="table">
|
||||
<a name="id674318"></a><p class="title"><b>Table<EFBFBD>3.<2E>Members of the [^boost::low_bits_mask_t] Class Template</b></p>
|
||||
<div class="table-contents"><table class="table" summary="Members of the [^boost::low_bits_mask_t] Class Template">
|
||||
<colgroup>
|
||||
<col>
|
||||
<col>
|
||||
</colgroup>
|
||||
<thead><tr>
|
||||
<th>
|
||||
<p>
|
||||
Member
|
||||
</p>
|
||||
</th>
|
||||
<th>
|
||||
<p>
|
||||
Meaning
|
||||
</p>
|
||||
</th>
|
||||
</tr></thead>
|
||||
<tbody>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">least</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
The smallest unsigned built-in type that supports the given bit count.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">fast</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
The quick-to-manipulate analog of <code class="literal">least</code>.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">sig_bits</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
A <code class="literal">least</code> constant of the desired bit-masking value.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">sig_bits_fast</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
A <code class="literal">fast</code> analog of <code class="literal">sig_bits</code>.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p>
|
||||
<code class="literal">bit_count</code>
|
||||
</p>
|
||||
</td>
|
||||
<td>
|
||||
<p>
|
||||
The value of the template parameter, in case its needed from a renamed
|
||||
instantiation of the class template.
|
||||
</p>
|
||||
</td>
|
||||
</tr>
|
||||
</tbody>
|
||||
</table></div>
|
||||
</div>
|
||||
<br class="table-break">
|
||||
</div>
|
||||
<div class="section" lang="en">
|
||||
<div class="titlepage"><div><div><h3 class="title">
|
||||
<a name="boost_integer.mask.implementation_notes"></a><a class="link" href="mask.html#boost_integer.mask.implementation_notes" title="Implementation Notes">Implementation
|
||||
Notes</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
||||
When <code class="literal">Bits</code> is the exact size of a built-in unsigned type,
|
||||
the implementation has to change to prevent undefined behavior. Therefore,
|
||||
there are specializations of <code class="literal">low_bits_mask_t</code> at those
|
||||
bit counts.
|
||||
</p>
|
||||
</div>
|
||||
<div class="section" lang="en">
|
||||
<div class="titlepage"><div><div><h3 class="title">
|
||||
<a name="boost_integer.mask.example"></a><a class="link" href="mask.html#boost_integer.mask.example" title="Example">Example</a>
|
||||
</h3></div></div></div>
|
||||
<pre class="programlisting"><span class="preprocessor">#include</span> <span class="special"><</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">integer</span><span class="special">/</span><span class="identifier">integer_mask</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">></span>
|
||||
|
||||
<span class="comment">//...
|
||||
</span>
|
||||
<span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
|
||||
<span class="special">{</span>
|
||||
<span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">high_bit_mask_t</span><span class="special"><</span><span class="number">29</span><span class="special">></span> <span class="identifier">mask1_type</span><span class="special">;</span>
|
||||
<span class="keyword">typedef</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">low_bits_mask_t</span><span class="special"><</span><span class="number">15</span><span class="special">></span> <span class="identifier">mask2_type</span><span class="special">;</span>
|
||||
|
||||
<span class="identifier">mask1_type</span><span class="special">::</span><span class="identifier">least</span> <span class="identifier">my_var1</span><span class="special">;</span>
|
||||
<span class="identifier">mask2_type</span><span class="special">::</span><span class="identifier">fast</span> <span class="identifier">my_var2</span><span class="special">;</span>
|
||||
<span class="comment">//...
|
||||
</span>
|
||||
<span class="identifier">my_var1</span> <span class="special">|=</span> <span class="identifier">mask1_type</span><span class="special">::</span><span class="identifier">high_bit</span><span class="special">;</span>
|
||||
<span class="identifier">my_var2</span> <span class="special">&=</span> <span class="identifier">mask2_type</span><span class="special">::</span><span class="identifier">sig_bits_fast</span><span class="special">;</span>
|
||||
|
||||
<span class="comment">//...
|
||||
</span><span class="special">}</span>
|
||||
</pre>
|
||||
</div>
|
||||
<div class="section" lang="en">
|
||||
<div class="titlepage"><div><div><h3 class="title">
|
||||
<a name="boost_integer.mask.demonstration_program"></a><a class="link" href="mask.html#boost_integer.mask.demonstration_program" title="Demonstration Program">Demonstration
|
||||
Program</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
||||
The program <a href="../../../test/integer_mask_test.cpp" target="_top">integer_mask_test.cpp</a>
|
||||
is a simplistic demonstration of the results from instantiating various examples
|
||||
of the bit mask class templates.
|
||||
</p>
|
||||
</div>
|
||||
<div class="section" lang="en">
|
||||
<div class="titlepage"><div><div><h3 class="title">
|
||||
<a name="boost_integer.mask.rationale"></a><a class="link" href="mask.html#boost_integer.mask.rationale" title="Rationale">Rationale</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
||||
The class templates in this header are an extension of the <a class="link" href="integer.html" title="Integer Type Selection">integer
|
||||
type selection class templates</a>. The new class templates provide the
|
||||
same sized types, but also convienent masks to use when extracting the highest
|
||||
or all the significant bits when the containing built-in type contains more
|
||||
bits. This prevents contaimination of values by the higher, unused bits.
|
||||
</p>
|
||||
</div>
|
||||
<div class="section" lang="en">
|
||||
<div class="titlepage"><div><div><h3 class="title">
|
||||
<a name="boost_integer.mask.credits"></a><a class="link" href="mask.html#boost_integer.mask.credits" title="Credits">Credits</a>
|
||||
</h3></div></div></div>
|
||||
<p>
|
||||
The author of the Boost bit mask class templates is <a href="http://www.boost.org/people/daryle_walker.html" target="_top">Daryle
|
||||
Walker</a>.
|
||||
</p>
|
||||
</div>
|
||||
</div>
|
||||
<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
|
||||
<td align="left"></td>
|
||||
<td align="right"><div class="copyright-footer">Copyright <20> 2001 -2009 Beman Dawes, Daryle Walker, Gennaro Prota,
|
||||
John Maddock<p>
|
||||
Distributed under the Boost Software License, Version 1.0. (See accompanying
|
||||
file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
|
||||
</p>
|
||||
</div></td>
|
||||
</tr></table>
|
||||
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|
||||
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Reference in New Issue
Block a user