index defaults to zero; a missing <code>high</code> index defaults to the length of the
sliced operand:
</p>

<pre>
a[2:]  // same as a[2 : len(a)]
a[:3]  // same as a[0 : 3]
a[:]   // same as a[0 : len(a)]
</pre>

<p>
If <code>a</code> is a pointer to an array, <code>a[low : high]</code> is shorthand for
<code>(*a)[low : high]</code>.
</p>

<p>

Thus <code>-2</code> is not the integer value minus two,
but the unsigned 64-bit integer with the same bit pattern.
The distinction rarely matters but
to avoid ambiguity, division or right shift where the right operand's
high bit is set is rejected.
</p>

<h3 id="symbols">Symbols</h3>

<p>
Some symbols, such as <code>R1</code> or <code>LR</code>,
are predefined and refer to registers.
The exact set depends on the architecture.

index defaults to zero; a missing <code>high</code> index defaults to the length of the
sliced operand:
</p>

<pre>
a[2:]  // same as a[2 : len(a)]
a[:3]  // same as a[0 : 3]
a[:]   // same as a[0 : len(a)]
</pre>

<p>
If <code>a</code> is a pointer to an array, <code>a[low : high]</code> is shorthand for
<code>(*a)[low : high]</code>.
</p>

<p>