Use PowerShell for REPL shell mode on Windows

[davidanthoff]

It would be great if the julia shell mode on Windows used PowerShell as the shell. That is after all the default shell on Windows, and it is much more powerful cmd.exe.

This has some info on how to host PowerShell. Not sure how one would pull this of technically, maybe have a mixed DLL that is compiled with VC as a bridge between julia and the CLR?

Clearly not a high priority item.

[yuyichao]

Dup of #7267 ?

[davidanthoff]

No, this is a different thing. What I'm suggesting here is that command entered in REPL mode of the julia shell (i.e. after you have pressed ;) are executed in a hosted PowerShell environment. #7267 is about the console that hosts the julia REPL. Two different things.

[tkelman]

It is however contained in #11478. I think it would be better to do this as a package rather than making it default, since there's a substantial initial latency in running powershell commands.

[davidanthoff]

Yes, #11478 has some discussion, but it really is a PR about something else, so might make sense to keep this issue here open?

I agree performance will not be good if you start powershell.exe whenever you execute a command via ;. I think the way to do this would be via the hosting API for PowerShell. Also agree that one could experiment with that in a package and then see how performances looks. If it is ok, it could go into base?

[tkelman]

I don't think we're likely to move much more functionality from packages into base, we're doing a lot of the reverse.

[tkelman]

If it's useful enough (and it probably would be for doing a more capable version of Base.download and others) then it could be a good candidate for a "default package," once we get the mechanism for doing that worked out.

[davidanthoff]

Did some more research on how this might be done. I think the easiest might be this: create a dll written in C# that interacts with the PowerShell hosting API. That dll would then export native functions via the UnmanagedExports package and could be called directly from julia via ccall. I just tried this and it all works. That seems by far the simplest way to get the whole CLR hosting etc. done, essentially one just gets that for free with this approach.

[PallHaraldsson]

"on Windows". Note, PowerShell is now portable to Linux and OS X. I guess it doesn't change this issue as can't depend on it installed..

[Bebotron]

Have there been any updates on this? I use Julia on Windows and it would be nice to use Powershell commands on the REPL in shell mode.

[StefanKarpinski]

We don't use a shell in any of the "shell" modes, so I'm inclined to say no on this.

[Bebotron]

Could you elaborate? I'm not quite familiar as to how shell mode works on the REPL. I just mean that just as we can use bash commands in shell mode running the REPL on Linux, is there no way to be able to use PS commands in shell mode on the REPL as well?

Edit: I guess I should clarify, it's not important to me that I can specifically use PS commands in shell mode. It would be perfectly ok to use bash commands. But the problem seems to be that when running the Julia REPL from Powershell, none of the usual commands work in shell mode (ls, pwd, cd, tec...)

[ViralBShah]

Has anyone tried if they work in git-bash?