How do I define a custom Ex command that forwards arguments with file completion?

Explanation

When you repeatedly type a long Ex command with filenames, define a user command that keeps the behavior but shortens the keystrokes. :command! -nargs=* -complete=file W w <args> creates a custom :W command that forwards all arguments to :w, including filename targets. This is practical for high-speed command-line workflows where you still want proper completion and argument handling.

How it works

• :command! defines (or force-redefines) a user command
• -nargs=* allows zero or more arguments after :W
• -complete=file enables filename completion when typing arguments
• W is the new command name
• w <args> is the implementation: it runs write with forwarded arguments

Examples after defining it:

:W
:W backup.txt
:W %:h/new-name.txt

Example

Before:

You often type: :w /tmp/scratch-output.txt

After defining the command:

You can type: :W /tmp/scratch-output.txt

The behavior is the same, but shorter and still completion-friendly.

Tips

• Use uppercase names to avoid clashing with built-in lowercase commands
• Add -bar if you want the command to allow trailing | command chaining
• Put custom commands in your config so they are available in every session