Duplicate a whole line in Vim

Question

How do I duplicate a whole line in Vim in a similar way to Ctrl+D in IntelliJ IDEA/Resharper or Ctrl+Alt+↑/↓ in Eclipse?

Answer 1

If you want another way :-)

"ayy this will store the line in buffer a

"ap this will put the contents of buffer a at the cursor.

There are many variations on this.

"a5yy this will store the 5 lines in buffer a

see http://www.vim.org/htmldoc/help.html for more fun

Answer 2

yy or Y to copy the line
or
dd to delete (cutting) the line

then

p to paste the copied or deleted text after the current line
or
P to paste the copied or deleted text before the current line

Answer 3

yyp - remember it with "yippee!"

Multiple lines with a number in between:

y7yp

Answer 4

Another option would be to go with:

nmap <C-d> mzyyp`z

gives you the advantage of preserving the cursor position.

Answer 5

For someone who doesn't know vi, some answers from above might mislead him with phrases like "paste ... after/before current line".
It's actually "paste ... after/before cursor".

yy or Y to copy the line
or
dd to delete the line

then

p to paste the copied or deleted text after the cursor
or
P to paste the copied or deleted text before the cursor

For more key bindings, you can visit this site: vi Complete Key Binding List

Answer 6

Default is yyp, but I've been using this rebinding for a year or so and love it:

" set Y to duplicate lines, works in visual mode as well. nnoremap Y yyp vnoremap Y y`>pgv