How do I use a macro to generate a numbered list automatically?

Explanation

By recording a macro that duplicates a line and increments its number, you can generate a numbered list of any length with a single replay command. The <C-a> key increments the number under the cursor, and repeating the macro builds the sequence automatically.

How it works

• qa starts recording into register a
• Y yanks the current line
• p pastes it below
• <C-a> increments the first number found on the line
• q stops recording
• 99@a replays the macro 99 times, generating 100 total lines

The macro will stop early if it encounters an error (like reaching a maxfuncdepth limit), but for simple numbered lists this pattern works flawlessly.

Example

Start with a single line:

1. Item

Record the macro with qaYp<C-a>q, then replay with 9@a to get:

1. Item
2. Item
3. Item
4. Item
5. Item
6. Item
7. Item
8. Item
9. Item
10. Item
11. Item

Or start with a more complex template:

test_case_1: assert_equal(expected_1, actual_1)

The macro increments every number on the line if you position <C-a> appropriately, or you can target specific numbers by adding motions before <C-a> in the recording.

Tips

• Use <C-x> instead of <C-a> to decrement numbers — useful for countdowns
• Add 0 before <C-a> in the macro to always move to the start of the line first, ensuring the correct number is incremented: qa Y p 0 <C-a> q
• For multiple numbers on one line, use a count or repeat <C-a>: 3<C-a> increments by 3
• Combine with visual block mode's g<C-a> for sequential incrementing without macros at all — select a column of identical numbers and g<C-a> turns them into a sequence
• If the line contains multiple numbers and you only want to increment a specific one, navigate to it with f or w before pressing <C-a> during recording
• Undo the entire generated list with u if the count was wrong, then replay with the correct count