Bug 19151 – std.utf.toUTF16z() can not be used for LPWSTR

The documentation of toUTF16z() (https://dlang.org/phobos/std_utf.html#toUTF16z) says that it can be used for LPWSTR or LPCWSTR. When compiling: auto success = CreateProcessW( null, commandLine.toUTF16z(), // <- error null, null, TRUE, CREATE_UNICODE_ENVIRONMENT, null, null, &startupInfo, &processInfo ); I got the compile error: source\process.d(32,32): Error: function `core.sys.windows.winbase.CreateProcessW(const(wchar)*, wchar*, SECURITY_ATTRIBUTES*, SECURITY_ATTRIBUTES*, int, uint, void*, const(wchar)*, STARTUPINFOW*, PROCESS_INFORMATION*)` is not callable using argument types `(typeof(null), const(wchar)*, typeof(null), typeof(null), int, uint, typeof(null), typeof(null), STARTUPINFOW*, PROCESS_INFORMATION*)` source\process.d(32,32): cannot pass argument `toUTF16z(cast(const(char)[])commandLine)` of type `const(wchar)*` to parameter `wchar*` Casting the second parameter to LPWSTR works. Using DMD 2.081.1 Maybe it relates to https://issues.dlang.org/show_bug.cgi?id=2275

I can confirm this. Not sure whether this workaround is right, but it works: commandLine.toUTFz!(wchar*)

The return type changed from wchar* to const(wchar*) ages ago, in a commit called "phobos-2.000". Git reports 10/09/2007, which seems to be the date of the migration from another RCS. https://github.com/dlang/phobos/commit/de971890b0c0780942857b92ec11168d827ef715#diff-27410a0be96392a06647e61c73131b64L797 Anyway, this is when toUTF16z stopped working for LPWSTR. Can toUTF16z be changed to use inout, maybe? Bastiaan.

@veelo created dlang/phobos pull request #6875 "toUTF16z cannot be used for LPWSTR." fixing this issue: - toUTF16z cannot be used for LPWSTR. Remove false statement from the documentation. Fixes issue 19151. https://github.com/dlang/phobos/pull/6875

dlang/phobos pull request #6875 "toUTF16z cannot be used for LPWSTR." was merged into master: - 9e5752313498999fa97a97d7d3d6adc8b7f74b33 by Bastiaan Veelo: toUTF16z cannot be used for LPWSTR. Remove false statement from the documentation. Fixes issue 19151. https://github.com/dlang/phobos/pull/6875