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<h2 id="moving-the-selection-with-syntax-aware-motions"><a class="header" href="#moving-the-selection-with-syntax-aware-motions">Moving the selection with syntax-aware motions</a></h2>
<p><code>Alt-p</code>, <code>Alt-o</code>, <code>Alt-i</code>, and <code>Alt-n</code> (or <code>Alt</code> and arrow keys) allow you to move the
selection according to its location in the syntax tree. For example, many languages have the
following syntax for function calls:</p>
<pre><code class="language-js">func(arg1, arg2, arg3);
</code></pre>
<p>A function call might be parsed by tree-sitter into a tree like the following.</p>
<pre><code class="language-tsq">(call
function: (identifier) ; func
arguments:
(arguments ; (arg1, arg2, arg3)
(identifier) ; arg1
(identifier) ; arg2
(identifier))) ; arg3
</code></pre>
<p>Use <code>:tree-sitter-subtree</code> to view the syntax tree of the primary selection. In
a more intuitive tree format:</p>
<pre><code> ┌────┐
│call│
┌─────┴────┴─────┐
│ │
┌─────▼────┐ ┌────▼────┐
│identifier│ │arguments│
│ "func" │ ┌────┴───┬─────┴───┐
└──────────┘ │ │ │
│ │ │
┌─────────▼┐ ┌────▼─────┐ ┌▼─────────┐
│identifier│ │identifier│ │identifier│
│ "arg1" │ │ "arg2" │ │ "arg3" │
└──────────┘ └──────────┘ └──────────┘
</code></pre>
<p>If you have a selection that wraps <code>arg1</code> (see the tree above), and you use
<code>Alt-n</code>, it will select the next sibling in the syntax tree: <code>arg2</code>.</p>
<pre><code class="language-js">// before
func([arg1], arg2, arg3)
// after
func(arg1, [arg2], arg3);
</code></pre>
<p>Similarly, <code>Alt-o</code> will expand the selection to the parent node, in this case, the
arguments node.</p>
<pre><code class="language-js">func[(arg1, arg2, arg3)];
</code></pre>
<p>There is also some nuanced behavior that prevents you from getting stuck on a
node with no sibling. When using <code>Alt-p</code> with a selection on <code>arg1</code>, the previous
child node will be selected. In the event that <code>arg1</code> does not have a previous
sibling, the selection will move up the syntax tree and select the previous
element. As a result, using <code>Alt-p</code> with a selection on <code>arg1</code> will move the
selection to the "func" <code>identifier</code>.</p>
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