Cross-platform shell scripts

V can be used as an alternative to Bash to write deployment scripts, build scripts, etc.

The advantage of using V for this is the simplicity and predictability of the language, and cross-platform support. "V scripts" run on Unix-like systems, as well as on Windows.

To use V's script mode, save your source file with the .vsh file extension. It will make all functions in the os module global (so that you can use mkdir() instead of os.mkdir(), for example).

V also knows to compile & run .vsh files immediately, so you do not need a separate step to compile them. V will also recompile an executable, produced by a .vsh file, only when it is older than the .vsh source file, i.e. runs after the first one, will be faster, since there is no need for a re-compilation of a script, that has not been changed.

An example deploy.vsh:

#!/usr/bin/env -S v // Note: The shebang line above, associates the .vsh file to V on Unix-like systems, // so it can be run just by specifying the path to the .vsh file, once it's made // executable, using `chmod +x deploy.vsh`, i.e. after that chmod command, you can // run the .vsh script, by just typing its name/path like this: `./deploy.vsh` // print command then execute it fn sh(cmd string) { println('❯ ${cmd}') print(execute_or_exit(cmd).output) } // Remove if build/ exits, ignore any errors if it doesn't rmdir_all('build') or {} // Create build/, never fails as build/ does not exist mkdir('build')? // Move *.v files to build/ result := execute('mv *.v build/') if result.exit_code != 0 { println(result.output) } sh('ls') // Similar to: // files := ls('.')? // mut count := 0 // if files.len > 0 { // for file in files { // if file.ends_with('.v') { // mv(file, 'build/') or { // println('err: ${err}') // return // } // } // count++ // } // } // if count == 0 { // println('No files') // }

Now you can either compile this like a normal V program and get an executable you can deploy and run anywhere:

v deploy.vsh && ./deploy

Or just run it more like a traditional Bash script:

v run deploy.vsh

On Unix-like platforms, the file can be run directly after making it executable using chmod +x:

./deploy.vsh

Vsh scripts with no extension

Whilst V does normally not allow vsh scripts without the designated file extension, there is a way to circumvent this rule and have a file with a fully custom name and shebang.

Whilst this feature exists, it is only recommended for specific use cases like scripts that will be put in the path and should not be used for things like build or deploy scripts.

To access this feature start the file with #!/usr/bin/env -S v -raw-vsh-tmp-prefix tmp where tmp is the prefix for the built executable.

This will run in crun mode, so it will only rebuild if changes to the script were made and keep the binary as tmp.<scriptfilename>.

If this filename already exists, the file will be overridden. If you want to rebuild each time and not keep this binary instead use #!/usr/bin/env -S v -raw-vsh-tmp-prefix tmp run.