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                            <h1 class="main">Trace</h1>
<p>Another feature of <code>v.debug</code> is the possibility to add hook functions
before and after each function call.</p>
<p>To enable this feature, add the <code>-d trace</code> switch when building or running
your code:</p>
<div class="language-v">import v.debug

fn main() {
    hook1 := debug.add_before_call(fn (fn_name string) {
        println('&gt; before ${fn_name}')
    })
    hook2 := debug.add_after_call(fn (fn_name string) {
        println('&gt; after ${fn_name}')
    })
    anon := fn () {
        println('call')
    }
    anon()

    // optionally you can remove the hooks:
    debug.remove_before_call(hook1)
    debug.remove_after_call(hook2)
    anon()
}
</div>
<pre><code>$ v -d trace run example.v
&gt; before anon
call
&gt; after anon
call
</code></pre>

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        //window.onload = () => {
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            //html.style.opacity = '1'
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    </script>


</body>

</html>