writing to closed stdout (I)

[kdevel]

On Sunday, 15 December 2024 at 13:51:31 UTC, kdevel wrote:
> ```sh
> $ dmd stdoutclosedsegfault
> $ ./stdoutclosedsegfault
> Segmentation fault
> ```

```
--- ./src/phobos/std/stdio.d_   2024-12-15 22:24:39.000000000 
+0100
+++ ./src/phobos/std/stdio.d    2024-12-15 22:30:00.000000000 
+0100
@@ -4252,6 +4252,7 @@
      {
          import std.exception : enforce;

+        enforce(.trustedStdout.isOpen, "Attempting to writeln() 
to closed file");
          enforce(fputc('\n', .trustedStdout._p.handle) != EOF, 
"fputc failed");
      }
      else static if (T.length == 1 &&
```

Im wondering, why `stdout.writeln ();` and `writeln ();` use 
different code. The former fragment will not segfault but throw

```
object.Exception at std/stdio.d(3144): Attempting to write to closed 
File
```