@zhuangtai-js/svelte

ZhuàngTài atom 的 Svelte 适配器。

@zhuangtai-js/svelte 把 @zhuangtai-js/core 的 atom 和 computed 转换为标准 Svelte store。它直接桥接 core 的同步 watch 与 Svelte store contract，不引入调度、批处理或 runes。

安装

npm install @zhuangtai-js/core @zhuangtai-js/svelte svelte
# 或
pnpm add @zhuangtai-js/core @zhuangtai-js/svelte svelte

@zhuangtai-js/core 和 svelte 都是 peer dependency。支持 core ^0.5.0，以及 Svelte 4.2 及以上版本和 Svelte 5。

使用

<script lang="ts">
  import { atom, computed } from "@zhuangtai-js/core";
  import { toReadable, toWritable } from "@zhuangtai-js/svelte";

  const countAtom = atom(0);
  const count = toWritable(countAtom);
  const double = toReadable(computed(() => countAtom.get() * 2));
</script>

<button on:click={() => count.update((value) => value + 1)}>
  {$count} × 2 = {$double}
</button>

转换后的对象是普通 Svelte store，可以用于 $store 自动订阅，也可以传给 derived、get、readonly 等 svelte/store API。

API

toReadable(source)

将 core 的 ReadableAtom<Value>（可写 atom 或 computed）转换为 Svelte Readable<Value>。

import { computed } from "@zhuangtai-js/core";
import { toReadable } from "@zhuangtai-js/svelte";

const double = toReadable(computed(() => countAtom.get() * 2));

toWritable(source)

将 core 的可写 Atom<Value> 转换为 Svelte Writable<Value>。

import { atom } from "@zhuangtai-js/core";
import { toWritable } from "@zhuangtai-js/svelte";

const countAtom = atom(0);
const count = toWritable(countAtom);

count.set(1);
count.update((value) => value + 1);

set 接收具体值并直接调用 core set。update 将 updater 交给 core set，因此 updater 总是接收执行时的最新值。

语义

• subscribe 只通过 core 的 watch 订阅。由于 watch 会同步发送当前值，subscriber 会在订阅时同步且仅同步运行一次。
• 初始 subscriber 运行前不会调用 invalidator；后续每次通知都会先调用可选 invalidator，再调用 subscriber。
• subscribe 返回 core watch 提供的 stopper；调用后立即停止后续通知。
• 所有通知与写入都保持同步，不添加调度、延迟、批处理或事务。
• adapter 不自行比较值。相等性完全由 core 的 Object.is 决定；对象和数组仍按引用判断，应使用不可变更新。
• adapter 不捕获或替换 core 与 subscriber 抛出的错误，错误传播语义保持不变。
• adapter 不使用 runes，也不创建跨 atom 的共享状态。

许可证

@zhuangtai-js/svelte 使用 ISC 许可证 发布。你可以自由使用、复制、修改和分发，但需要在副本中保留版权声明和许可证声明。

@zhuangtai-js/svelte

Svelte adapter for ZhuàngTài atoms.

@zhuangtai-js/svelte converts @zhuangtai-js/core atoms and computeds into standard Svelte stores. It bridges core's synchronous watch directly to the Svelte store contract, without adding scheduling, batching, or runes.

Install

npm install @zhuangtai-js/core @zhuangtai-js/svelte svelte
# or
pnpm add @zhuangtai-js/core @zhuangtai-js/svelte svelte

Both @zhuangtai-js/core and svelte are peer dependencies. Core ^0.5.0 and Svelte 4.2+ and 5 are supported.

Usage

<script lang="ts">
  import { atom, computed } from "@zhuangtai-js/core";
  import { toReadable, toWritable } from "@zhuangtai-js/svelte";

  const countAtom = atom(0);
  const count = toWritable(countAtom);
  const double = toReadable(computed(() => countAtom.get() * 2));
</script>

<button on:click={() => count.update((value) => value + 1)}>
  {$count} × 2 = {$double}
</button>

The converted objects are ordinary Svelte stores. They work with $store auto-subscriptions and can be passed to derived, get, readonly, and other svelte/store APIs.

API

toReadable(source)

Converts a core ReadableAtom<Value> (a writable atom or a computed) into a Svelte Readable<Value>.

import { computed } from "@zhuangtai-js/core";
import { toReadable } from "@zhuangtai-js/svelte";

const double = toReadable(computed(() => countAtom.get() * 2));

toWritable(source)

Converts a writable core Atom<Value> into a Svelte Writable<Value>.

import { atom } from "@zhuangtai-js/core";
import { toWritable } from "@zhuangtai-js/svelte";

const countAtom = atom(0);
const count = toWritable(countAtom);

count.set(1);
count.update((value) => value + 1);

set accepts a concrete value and calls core set directly. update passes its updater to core set, so the updater always receives the latest value at execution time.

Semantics

• subscribe subscribes only through core watch. Because watch synchronously emits the current value, the subscriber runs synchronously exactly once during subscription.
• The invalidator is not called before the initial subscriber run. Every later notification calls the optional invalidator before the subscriber.
• subscribe returns the stopper provided by core watch; calling it immediately stops later notifications.
• All notifications and writes remain synchronous. No scheduling, deferring, batching, or transactions are added.
• The adapter performs no value comparison. Equality is entirely core's Object.is; objects and arrays remain reference-based and should be updated immutably.
• The adapter does not catch or replace errors thrown by core or subscribers, preserving their propagation semantics.
• The adapter uses no runes and creates no shared state across atoms.

License

@zhuangtai-js/svelte is released under the ISC License. You may use, copy, modify, and distribute it freely, provided that the copyright notice and license notice are retained in copies.