@networkpro/web
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This package powers the official web presence of Network Pro Strategies — a research- and infrastructure-focused technology initiative working across cybersecurity, digital systems, and privacy.
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> [!NOTE] `$inspect` only works during development. In a production build it becomes a noop.
The `$inspect` rune is roughly equivalent to `console.log`, with the exception that it will re-run whenever its argument changes. `$inspect` tracks reactive state deeply, meaning that updating something inside an object or array using fine-grained reactivity will cause it to re-fire (demo:
```svelte
<script>
let count = $state(0);
let message = $state('hello');
$inspect(count, message); // will console.log when `count` or `message` change
</script>
<button onclick={() => count++}>Increment</button>
<input bind:value={message} />
```
On updates, a stack trace will be printed, making it easy to find the origin of a state change (unless you're in the playground, due to technical limitations).
## $inspect(...).with
`$inspect` returns a property `with`, which you can invoke with a callback, which will then be invoked instead of `console.log`. The first argument to the callback is either `"init"` or `"update"`; subsequent arguments are the values passed to `$inspect` (demo:
```svelte
<script>
let count = $state(0);
$inspect(count).with((type, count) => {
if (type === 'update') {
debugger; // or `console.trace`, or whatever you want
}
});
</script>
<button onclick={() => count++}>Increment</button>
```
## $inspect.trace(...)
This rune, added in 5.14, causes the surrounding function to be _traced_ in development. Any time the function re-runs as part of an [effect]($effect) or a [derived]($derived), information will be printed to the console about which pieces of reactive state caused the effect to fire.
```svelte
<script>
import { doSomeWork } from './elsewhere';
$effect(() => {
+++// $inspect.trace must be the first statement of a function body+++
+++$inspect.trace();+++
doSomeWork();
});
</script>
```
`$inspect.trace` takes an optional first argument which will be used as the label.