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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> </main> <nav class="nav-wrapper" aria-label="Page navigation"> <!-- Mobile navigation buttons --> <a rel="prev" href="textobjects.html" class="mobile-nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> <i class="fa fa-angle-left"></i> </a> <a rel="next prefetch" href="pickers.html" class="mobile-nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> <i class="fa fa-angle-right"></i> </a> <div style="clear: both"></div> </nav> </div> </div> <nav class="nav-wide-wrapper" aria-label="Page navigation"> <a rel="prev" href="textobjects.html" class="nav-chapters previous" title="Previous chapter" aria-label="Previous chapter" aria-keyshortcuts="Left"> <i class="fa fa-angle-left"></i> </a> <a rel="next prefetch" href="pickers.html" class="nav-chapters next" title="Next chapter" aria-label="Next chapter" aria-keyshortcuts="Right"> <i class="fa fa-angle-right"></i> </a> </nav> </div> <script> window.playground_copyable = true; </script> <script src="elasticlunr.min.js"></script> <script src="mark.min.js"></script> <script src="searcher.js"></script> <script src="clipboard.min.js"></script> <script src="highlight.js"></script> <script src="book.js"></script> <!-- Custom JS scripts --> </div> </body> </html>