How do I apply the last substitution's replacement to a different search pattern without retyping it?

Explanation

The :~ command repeats the last substitution but uses the current search pattern instead of the original pattern. This lets you reuse the same replacement text across different searches — without retyping the replacement.

How it works

• & — repeat last :s with the exact same search and replacement
• :~ — repeat last :s with the last search (/) as the find pattern, keeping the same replacement

So if you last ran :s/FIXME/RESOLVED/ and then searched /TODO, running :~ executes :s/TODO/RESOLVED/.

Example

Start with a file containing two different markers:

FIXME: broken auth
TODO: refactor this

Run a substitution on the first marker:

:s/FIXME/DONE/

Now search for the second marker:

/TODO

Instead of retyping the replacement, repeat with the new pattern:

:~

Result: TODO: refactor this becomes DONE: refactor this.

Tips

• Append g to replace all occurrences on the line: :~g
• Use a range: :1,50~g to restrict to lines 1–50 with the current search
• The companion & repeats the same :s exactly, and g& applies it file-wide
• This is especially handy when doing a batch cleanup with the same replacement across many different patterns