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Comment by nikomatsakis | Hacker News Reader

You're missing something. The semantics of `ret` are always consistent: it always returns from out the innermost `fn()` declaration (closures written using the sugared notation `{||...}` do not count as fn declarations, but closures written as `fn() { ... }` do). In cases where this is not possible, a static error is generated.

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So what happens if we pass a stack closure containing a ret into another function? For example, what would this code print out:

  fn foo(f: fn()) {
    log(info, "calling f");
    f();
    log(info, "called f");
  }

  fn bar() {
    log(info, "calling foo");
    foo({||
      ret;
    });
    log(info, "called foo");
  }

I'm not clear on whether the ret would return from foo or from bar - or whether it would be a compile error.

BTW thanks for taking the time to reply - I appreciate it!

Tried compiling this myself with a main function that just calls bar(), resulting in a compiler error:

  `ret` in block function

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