How do I paste from a register in insert mode without Vim interpreting special characters?

Explanation

In insert mode, <C-r>{reg} pastes from a register but treats certain bytes as key inputs — so a register containing \n triggers a newline, \x08 triggers backspace, and so on. This causes surprising edits when pasting content with embedded control characters or multi-line text.

Using <C-r><C-r>{reg} (double Ctrl-R) inserts the register's content literally — every byte is inserted as a character, with no interpretation. It is the insert-mode equivalent of :put without the newline semantics.

How it works

• <C-r>{reg} — paste register; special bytes are acted on (can trigger commands or modify the buffer unexpectedly)
• <C-r><C-r>{reg} — paste register literally; all bytes inserted as-is

A third variant, <C-r><C-o>{reg}, pastes literally and does not auto-indent — useful when autoindent or smartindent would mangle the pasted block.

Example

Suppose register a contains foo\nbar (a literal newline in the middle). In insert mode:

<C-r>a  → inserts two lines (newline is interpreted as Enter)
<C-r><C-r>a  → inserts the literal string including the newline char, staying on one line

This matters when building search patterns, command arguments, or string literals where control characters must be verbatim.

Tips

• Use <C-r><C-o>" to paste the unnamed register literally without auto-indent — ideal for code blocks in files with autoindent on
• The same <C-r><C-r> trick works in command-line mode (:) to paste register content into an Ex command literally
• Check a register's raw content with :reg {name} before pasting to see if it contains control characters