protection from infinite loops • Playground • Svelte

App.svelte

let count = 1;

$: if (count) count++;

</script>

<h1>Count is {count}!</h1>

<button on:click={() => count++}>

clicking won't cause an infinite loop

</button>

import 'svelte/internal/disclose-version';

import 'svelte/internal/flags/legacy';

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

var root = $.template(`<h1> </h1> <button>clicking won't cause an infinite loop</button>`, 1);

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

$.push($$props, false);

let count = $.mutable_state(1);

$.legacy_pre_effect(() => ($.get(count)), () => {

if ($.get(count)) $.update(count);

});

$.legacy_pre_effect_reset();

var fragment = root();

var h1 = $.first_child(fragment);

var text = $.child(h1);

$.reset(h1);

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

$.template_effect(() => $.set_text(text, `Count is ${$.get(count) ?? ''}!`));

$.event('click', button, () => $.update(count));

$.append($$anchor, fragment);

$.pop();

}

result = svelte.compile(source, {

generate: "client" "server",

dev: false });

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

		
			
				
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js: []
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raw: "!"
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raw: " "
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 }
end:  {...}
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expression: true
generator: false
async: false
params: []
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fragment: Fragment {...}
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nodes: [...] (1)
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data: "clicking won't cause an infinite loop"
 }
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options: null
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context: "default"
content: Program {...}
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kind: "let"
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 LabeledStatement {...}
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name: "count"
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consequent: ExpressionStatement {...}
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expression: UpdateExpression {...}
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loc:  {...}
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 }
 }
operator: "++"
prefix: false
argument: Identifier {...}
 type: "Identifier"
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loc:  {...}
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 }
end:  {...}
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name: "count"
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alternate: null
 }
label: Identifier {...}
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name: "$"
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sourceType: "module"
 }
attributes: []
 }
 }

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

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