How do I convert a register's type between characterwise and linewise?

Explanation

Registers in Vim have a type — characterwise, linewise, or blockwise — that affects how their contents are pasted. Using setreg(), you can change a register's type without modifying its content, controlling whether paste inserts inline or on new lines.

How it works

• setreg({reg}, {value}, {type}) — set register with explicit type
• Type flags: 'c' = characterwise, 'l' = linewise, 'b' = blockwise
• getregtype({reg}) — returns the current type: v, V, or \x16{width}

Example

" Yank a word (characterwise by default)
yiw
" Convert unnamed register to linewise
:call setreg('"', @", 'l')
" Now p pastes on a new line instead of inline

Before conversion: p inserts 'word' inline
After conversion:  p inserts 'word' on a new line below

Tips

• Check register type: :echo getregtype('a') returns v, V, or ^V{n}
• Blockwise type includes width: setreg('a', text, 'b10') for 10-char wide block
• Use getreg('a', 1, 1) to get register content as a list of lines
• This is essential when writing plugins that need consistent paste behavior