[Issue 24208] [DIP1000] Nested function can escape scope parameter

[d-bugmail--- via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=24208

--- Comment #3 from Paul Backus  ---
Disregard previous example, I read the errors wrong. They occur in the function
bodies, not at the call site. The parameter of `escape` is not allowed to
escape at all if it is `scope`, even `return scope`.

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[Issue 24208] [DIP1000] Nested function can escape scope parameter

[d-bugmail--- via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=24208

--- Comment #2 from Paul Backus  ---
...or maybe the problem is that it's being incorrectly inferred as `scope`
instead of `return scope`.

Another example:

---
void main() @safe
{
int* escaped;

void escape1(int* p) @safe
{
escaped = p;
}

void escape2(scope int* p) @safe
{
escaped = p;
}

void escape3(return scope int* p) @safe
{
escaped = p;
}

int n;
escape1(); // no error
escape2(); // error
escape3(); // error
}
---

It's hard to tell what attributes the compiler is inferring here, but the
observed behavior is consistent with the hypothesis that `scope int* p` is
being inferred for `escape1`, and `return scope int* p` is being inferred for
both `escape2` and `escape3`.

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[Issue 24208] [DIP1000] Nested function can escape scope parameter

[d-bugmail--- via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=24208

Paul Backus  changed:

   What|Removed |Added

Summary|[DIP1000] Nested function   |[DIP1000] Nested function
   |can pass scope pointer to   |can escape scope parameter
   |non-scope parameter |

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