WSL

The wsl module crosses between Windows and WSL Linux using a block-scoped stdio VFS.

Direction	Required starting target	Destination helper	Path style
Windows → Linux	Windows, with `wsl.exe`	`dolang-vfs` in the distribution	Unix
WSL Linux → Windows	Linux with WSL interoperability	`dolang-vfs.exe`, or `dolang.exe --vfs`	Windows

Entering Linux from Windows

with_linux starts dolang-vfs in a WSL distribution. The distribution and user are optional:

import wsl sys

wsl.with_linux distro: Ubuntu user: builder do
  echo $sys.os_info().os
  run uname -a

The selected distribution must provide dolang-vfs in its command search path. Use command: to supply another launcher prefix.

Entering Windows from WSL

with_windows uses WSL executable interoperability:

import wsl sys

wsl.with_windows do
  echo $sys.os_info().os
  run cmd.exe /c ver

It prefers dolang-vfs.exe and falls back to dolang.exe --vfs. Both are resolved through the active Linux environment's PATH. Use command: to override discovery.

When the interpreter originally started on Windows, prefer shell.with_host to return temporarily from a nested Linux VFS. with_windows is intended for an interpreter that started within WSL and has no Windows startup context to restore.

Windows UAC elevation composes with the transition:

import wsl admin

wsl.with_windows do
  admin.with do
    do_something()

Directory and Environment Overrides

Both functions accept cd: and env:. These describe the destination, so use an UnixPath when entering Linux and a WindowsPath when entering Windows if the path must be constructed before entering that context, or use ordinary strings.

Environment keys may be strings or symbols. A nil value unsets the variable; :INHERIT: copies its current value before crossing the boundary.

Override value	Destination behavior
Key omitted	Keep the helper's inherited destination value
`nil`	Unset the variable
`:INHERIT:`	Copy the current source value, or unset it if absent
Other value	Set its string representation explicitly

The destination VFS is stopped when the block returns or throws.