问HN:如果一种语言的结构决定了内存的生命周期,会怎样?

4作者: stevendgarcia大约 1 个月前原帖
我一直在探索一种新的系统语言设计,围绕着一个严格的原则构建: 数据的生命周期与创建它的词法作用域完全一致。 外部作用域永远不能保留对内部分配的引用。 没有垃圾回收(GC)。 没有传统的Rust风格借用检查器。 没有隐式生命周期。 没有隐式引用计数。 当一个作用域退出时,内部分配的所有内容都会被确定性地释放。 --- 以下是代码中的基本思想: ```rust fn handler() { let user = load_user(); // 任务作用域分配 CACHE.set(user); // 编译错误:从内部作用域逃逸 CACHE.set(user.clone()); // 显式逃逸 } ``` 如果数据需要逃逸作用域,必须显式地克隆或移动。 编译器在编译时强制执行这些边界。 没有运行时的生命周期检查。 内存管理成为一种结构不变式。 程序结构使得错误使用无法表示,而不是依赖于运行时跟踪生命周期。 并发遵循相同的封闭规则。 ```rust fn fetch_all(ids: [Id]) -> Result<[User]> { parallel { let users = fetch_users(ids)?; let prefs = fetch_prefs(ids)?; } merge(users, prefs) } ``` 如果任何分支失败,整个并行作用域将被取消,内部的所有分配都会被确定性地释放。 这在字面意义上是结构化并发: 当一个并行作用域退出(成功或失败)时,其内存会自动清理。 失败和重试也是显式控制流,而不是异常状态: ```rust let result = restart { process_request(req)? } ``` 重启会丢弃整个作用域,并从干净的状态重新尝试。 没有部分状态。 没有手动清理逻辑。 --- 我认为这有意义的不同之处在于: 该模型是围绕封闭性构建的,而不是熵。 某些不安全状态的防止不是依靠约定或纪律,而是依靠结构。 这消除了: * 隐式生命周期和隐藏的内存管理 * 内存泄漏和悬空指针(作用域是所有者) * 跨不相关生命周期的共享可变状态 如果数据必须比作用域活得更久,这一事实必须在代码中显式体现。 --- 在这个阶段我想要学习的内容: 1. 可扩展性。这个模型能否在长时间运行的高性能服务器中工作,而不依赖于GC或普遍的引用计数? 2. 效果隔离。I/O和副作用应如何与基于作用域的重试或取消交互? 3. 代际句柄。这个模型能否在不造成过多开销的情况下替代传统借用? 4. 失败模式。与Rust、Go或Erlang相比,这个模型在哪些方面会崩溃? 5. 可用性。哪些常见模式变得不可能,这些是有用的约束还是致命缺陷? --- 一些额外的想法,仍在探索中: * 具有时代风格管理的结构化并发(没有全局原子操作) * 每个核心严格固定的执行区域,具有无锁分配 * 仅在崩溃时重试,失败总是丢弃整个作用域 --- 但核心问题是: 像这样的严格作用域封闭内存模型在实践中真的能有效工作吗,而不会悄然重新引入GC或传统的生命周期机制? 注意:这并不是“Rust但不同”或对旧系统的怀旧。 这是探索一种根本不同的思维方式来理解内存和并发的尝试。 我非常希望能得到关于这个模型的批评反馈——它在哪些方面有效,在哪些方面崩溃。 感谢阅读。
查看原文
I’ve been exploring a new systems-language design built around a single hard rule:<p>Data lives exactly as long as the lexical scope that created it.<p>Outer scopes can never retain references to inner allocations.<p>There is no GC.<p>No traditional Rust-style borrow checker.<p>No hidden lifetimes.<p>No implicit reference counting.<p>When a scope exits, everything allocated inside it is freed deterministically.<p>---<p>Here’s the basic idea in code:<p><pre><code> fn handler() { let user = load_user() &#x2F;&#x2F; task-scoped allocation CACHE.set(user) &#x2F;&#x2F; compile error: escape from inner scope CACHE.set(user.clone()) &#x2F;&#x2F; explicit escape } </code></pre> If data needs to escape a scope, it must be cloned or moved explicitly.<p>The compiler enforces these boundaries at compile time. There are no runtime lifetime checks.<p>Memory management becomes a structural invariant. Instead of the runtime tracking lifetimes, the program structure makes misuse unrepresentable.<p>Concurrency follows the same containment rules.<p><pre><code> fn fetch_all(ids: [Id]) -&gt; Result&lt;[User]&gt; { parallel { let users = fetch_users(ids)? let prefs = fetch_prefs(ids)? } merge(users, prefs) } </code></pre> If any branch fails, the entire parallel scope is cancelled and all allocations inside it are freed deterministically.<p>This is structured concurrency in the literal sense: when a parallel scope exits (success or failure), its memory is cleaned up automatically.<p>Failure and retry are also explicit control flow, not exceptional states:<p><pre><code> let result = restart { process_request(req)? } </code></pre> A restart discards the entire scope and retries from a clean slate.<p>No partial state.<p>No manual cleanup logic.<p>---<p>Why I think this is meaningfully different:<p>The model is built around containment, not entropy. Certain unsafe states are prevented not by convention or discipline, but by structure.<p>This eliminates:<p>* Implicit lifetimes and hidden memory management<p>* Memory leaks and dangling pointers (the scope is the owner)<p>* Shared mutable state across unrelated lifetimes<p>If data must live longer than a scope, that fact must be made explicit in the code.<p>---<p>What I’m trying to learn at this stage:<p>1. Scalability. Can this work for long-running, high-performance servers without falling back to GC or pervasive reference counting?<p>2. Effect isolation. How should I&#x2F;O and side effects interact with scope-based retries or cancellation?<p>3. Generational handles. Can this replace traditional borrowing without excessive overhead?<p>4. Failure modes. Where does this model break down compared to Rust, Go, or Erlang?<p>5. Usability. What common patterns become impossible, and are those useful constraints or deal-breakers?<p>---<p>Some additional ideas under the hood, still exploratory:<p>* Structured concurrency with epoch-style management (no global atomics)<p>* Strictly pinned execution zones per core, with lock-free allocation<p>* Crash-only retries, where failure always discards the entire scope<p>---<p>But the core question comes first:<p>Can a strictly scope-contained memory model like this actually work in practice, without quietly reintroducing GC or traditional lifetime machinery?<p>NOTE: This isn’t meant as “Rust but different” or nostalgia for old systems.<p>It’s an attempt to explore a fundamentally different way of thinking about memory and concurrency.<p>I’d love critical feedback on where this holds up — and where it collapses.<p>Thanks for reading.