How do I copy a character from the line above or below while in insert mode?

Explanation

When typing in insert mode, you can pull individual characters from adjacent lines without leaving insert mode. <C-y> copies the character directly above the cursor, and <C-e> copies the character directly below. This is invaluable when you need to type something nearly identical to a neighboring line.

How it works

• <C-y> — inserts the character from the same column on the line above the cursor
• <C-e> — inserts the character from the same column on the line below the cursor
• Each press copies one character; hold or press repeatedly to copy multiple characters in sequence
• If the adjacent line is shorter than the current cursor column, nothing is inserted

Example

Suppose you are writing similar configuration lines:

server_host = "production.example.com"
server_port = "8443"

While on the second line in insert mode, pressing <C-y> repeatedly after typing server_ would pull characters from the line above one at a time: h, o, s, t... letting you reuse the structure without copy-pasting.

Tips

• Particularly useful for aligned tabular data, similar variable names, or repetitive code patterns
• Combine with regular typing — pull a few characters from above, then type the part that differs
• Works alongside <C-n>/<C-p> word completion for different granularities of reuse