multiple changes per tick are ignored • Playground • Svelte

App.svelte

let name = "Sarah";

let countChanges = 0;

$: {

console.log("I run whenever the name changes!", name);

countChanges++;

}

name = "John";

name = "Another name that will be ignored?";

console.log("the name was indeed", name)

name = "Rose";

</script>

<h1>Hello {name}!</h1>

<p>

I think that name has changed {countChanges} times

</p>

the name was indeed Another name that will be ignored?

I run whenever the name changes! Rose

import 'svelte/internal/disclose-version';

import 'svelte/internal/flags/legacy';

import * as $ from 'svelte/internal/client';

var root = $.template(`<h1> </h1> <p> </p>`, 1);

export default function App($$anchor, $$props) {

$.push($$props, false);

let name = $.mutable_state("Sarah");

let countChanges = $.mutable_state(0);

$.set(name, "John");

$.set(name, "Another name that will be ignored?");

console.log("the name was indeed", $.get(name));

$.set(name, "Rose");

$.legacy_pre_effect(() => ($.get(name), $.get(countChanges)), () => {

console.log("I run whenever the name changes!", $.get(name));

$.update(countChanges);

});

$.legacy_pre_effect_reset();

var fragment = root();

var h1 = $.first_child(fragment);

var text = $.child(h1);

$.reset(h1);

var p = $.sibling(h1, 2);

var text_1 = $.child(p);

$.reset(p);

$.template_effect(() => {

result = svelte.compile(source, {

generate: "client" "server",

dev: false });

/* Add a <style> tag to see the CSS output */

		
			
				
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sourceType: "module"
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attributes: []
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 }

The AST is not public API and may change at any point in time

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