https://forum.dlang.org/post/j8nnr2$bgf$1@digitalmars.com

On Tuesday, 1 November 2011 at 03:08:18 UTC, Kapps wrote:

I interest this too.
Theme up.

    int opApply( scope int delegate( FT_Outline outline ) dg )
    {
        // ...more code...
        return 0;
    }


    void main()
    {
        // ...initialization code...

        foreach ( outl; outline )
        {
            writeln( outl );
        }
    }

I tested this code in Compiler Explorer: https://godbolt.org/z/vnqoYsazn

With default options LDC do call the example.FT_Outline.opApply.

But with -O and when function opApply() marked as pragma( inline, true ) then LDC put opApply() body inline. I see call writeln() directly from _Dmain, without call/ret | jmp.

LDC can put foreach body inline. But need to test with real-world application.