Vimscript - split function call to multiple lines

Question

I'm trying to write a vimscript that converts a line like this:

    myFuncCall(param1, param2, param3="hey", param4)

To:

    myFuncCall(param1,
        param2,
        param3="hey",
        param4
    )

While maintaining and adding indentation. So far I have:

function SplitParamLines() abort
    let f_line_num = line(".")
    let indent_length = indent(f_line_num)
    echom indent_length
    echom f_line_num
    .s/\s*,/,\r/g
    nohlsearch
    0t)a<cr>
endfunction

How do I indent lines using vimscript?

Why does the last line produces this?:

Error detected while processing function SplitParamLines:
line    7:
E14: Invalid address

Answer 1

So there are 2 options which I chose to use both:

1. Using this incredible plugin - Splitjoin.vim
2. Using this simple function:

" Every parameter in its own line
function SplitParamLines() abort
    let f_line_num = line(".")
    let indent_length = indent(f_line_num)
    exe ".s/\s*,/,\r" . repeat(" ", indent_length + &shiftwidth - 1) . "/g"
    nohlsearch
    " execute "normal! 0t)a\<cr>\<esc>"
endfunction
nnoremap <silent> <leader>( :call SplitParamLines()<cr>

Although not perfect, it works :)

Answer 2

If you want to execute something that you would have typed, you need :normal. If there are special characters, then you'll also need :exe and to escape these special characters. IOW

:exe "normal! 0t)i\<cr>"