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<h4 class="subsection" id="Hexadecimal-and-Binary-Integer-Constants-1"><span>4.4.1 Hexadecimal and Binary Integer Constants<a class="copiable-link" href="#Hexadecimal-and-Binary-Integer-Constants-1"> ¶</a></span></h4>
<p>The use of hexadecimal or binary notation to define a number will automatically
create an unsigned integer using a representation that is just large enough to
hold the specified value. For example:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">0b101 # uint8
0x100 # uint16
0xDEADBEEF # uint32
0x1DEADBEEF # uint64
</pre></div></div>
<p>The storage class can be specified by adding a suffix. Use ‘<samp class="samp">s</samp>’ for signed
integers and ‘<samp class="samp">u</samp>’ for unsigned integers along with a size (‘<samp class="samp">8</samp>’,
‘<samp class="samp">16</samp>’, ‘<samp class="samp">32</samp>’, ‘<samp class="samp">64</samp>’). The use of the underscore separator ‘<samp class="samp">_</samp>’
can improve readability. For example:
</p>
<div class="example">
<div class="group"><pre class="example-preformatted">0b101s16 # int16
0b101_s16 # int16, value and representation separated
0xDEADBEEFs32 # int32
0xDEADBEEF_u64 # uint64
</pre></div></div>
<p>Note that when defining matrices of integer constants the overall matrix will
have the storage class of its first element. The matrix
<code class="code">[0x1; 0x100; 0x10000]</code> will be of type <code class="code">uint8</code> and the larger values
will be truncated because of the saturation semantics of integer values. To
avoid this issue either: 1) declare the first integer to be of the desired size
such as <code class="code">0x1u32; 0x100; 0x10000]</code>, or 2) pad constants in array
expressions with leading zeros so that they use the same number of digits for
each value such as <code class="code">[0x00_00_01; 0x00_01_00; 0x01_00_00]</code>.
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