Copy block of code with increasing index - vim

Question

I have the following function declaration:
function f1(s)
real f1,s
f1 = 1/s
end
I would like to copy the same block but with increasing function name, i.e. f1, f2, f3, ... in order to get this:
function f1(s)
real f1,s
f1 = 1/s
end
function f2(s)
real f2,s
f2 = 1/s
end
function f3(s)
real f3,s
f3 = 1/s
end
My present approach is to copy the block in visual mode, paste it several times and then rename the functions manually. I would like to know how to achieve this faster using Vim. Thanks.

Answer 1

You can always use a recording (see :h recording). Assuming you have a blank line before and after your function and no blank lines in between
// empty line here, cursor here
function f1(s)
real f1,s
f1 = 1/s
end
// empty line here
With the cursor on the empty line above, make a recording to any register you like. Here I'm using register c. Press qc then press y}}Pjw*Ne^Ane^Ane^A{ and exit with q.
Explanation
y} - yank next paragraph
} - move down one paragraph
P - put above this line
j - move one line done
w - move to next word
* - search for word under cursor ( this is the function name here)
N - search backwards ( we moved with * to get the pattern into the register )
e - go to end of word
^A - Ctrl a to increase the number
n - go to next match / search forward ( this is the function name )
e - go to end of word
^A - increase the number
n - go to next match / search forward
e - go to end of word
^A - increase the number
{ - move up one paragraph (same relative position as in the beginning, but at the inserted function f2 )
Now you can use #c to copy the function and increase all numbers. Prefix with the count you want, e.g. 5#c will copy the function 5 times and adjust the numbering.
In case you don't want to remember the string y}}Pjw*Ne^Ane^Ane^A{ you can paste it in the vim buffer. You will have to replace the ^A before yanking though. Delete ^A and when in insert mode press Ctrl va. ( If you are inside a screen session you will have to press Ctrl aa, this is CTRL-a and a)
With the cursor on the line in normal mode press "cY to yank it in register c.
Then you can replay it with #c.
This way you can also modify it or yank it to another register.
Use let #c=y}}Pjw*Ne^Ane^Ane^A{ in your .vimrc to have it always load to register c when starting vim.

Answer 2

I figured out the solution. It may seems complex but does not, cause you have just to copy this function to the clipboard and load the function with:
:#+
Below the function with additional features
fun! CopyAndIncrease()
try
let l:old_copy = getreg('0')
normal yip
let #0 = substitute(#0,'\d\+','\=submatch(0) + 1','g')
exec "normal }O\<Esc>p"
finally
call setreg('0', l:old_copy)
endtry
endfun
command! -nargs=0 CopyIncrease silent call CopyAndIncrease() | exec "normal \<Esc>"
let mapleader = ','
nnoremap <Leader>c :CopyIncrease<CR>
Now pressing ,c Now you can use the keybinding and commands defined in the function.
Function's explanation:
let l:old_copy = getreg('0') -> save copy register
normal yip -> copy block
let #0 ... increase numbers on copy register
exec "normal }O\<Esc>p" -> paste increased block