[Issue 16551] New: Compile-time delegate parameters should allow "scope"

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16551

          Issue ID: 16551
           Summary: Compile-time delegate parameters should allow "scope"
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: eyal at weka.io

Currently, in order to pass scoped delegates and avoid GC, one must pass the
delegates as run-time parameters, with undesirable consequences.

It would be very helpful to allow them to be passed as scoped and in
compile-time.

alias Foo1 = void delegate() @nogc;
alias Foo2 = scope void delegate() @nogc; // <-- this "scope" seems to be
completely ignored!

// Syntax error, why? :(
// void foo(scope Foo1 x)() @nogc;

// This is allowed, but Foo2 is not truly "scope"
void foo(Foo2 x)() @nogc;

void main() @nogc {
    int x;
    foo!({x+=1;}); // Claims to allocate with the gc, it does not!
}

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