How to 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+&

Answer 1

Normal mode: see other answers.

The Ex way:

• :t. will duplicate the line,
• :t 7 will copy it after line 7,
• :,+t0 will copy current and next line at the beginning of the file (,+ is a synonym for the range .,.+1),
• :1,t$ will copy lines from beginning till cursor position to the end (1, is a synonym for the range 1,.).

If you need to move instead of copying, use :m instead of :t.

This can be really powerful if you combine it with :g or :v:

• :v/foo/m$ will move all lines not matching the pattern “foo” to the end of the file.
• :+,$g/^\s*class\s\+\i\+/t. will copy all subsequent lines of the form class xxx right after the cursor.

Reference: :help range, :help :t, :help :g, :help :m and :help :v