How to join lines within a block with `J`?

Question

I want to join all the lines within a {} block.

{
  'a': 1,
  'b': 2,
  'c': 3,
}

⬇︎

{ 'a': 1, 'b': 2, 'c': 3, }

Since J doesn't take a range, like d or c, the best command I found to do this is going through virtual mode: Va{J.

Is there a nicer way to do the same?

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This is not a duplicated of Why doesn't gJip turn a paragraph into a line? since that question doesn't ask how to turn a paragraph into a line. The proper answer of that question is "gJ doesn't work like that".

Answer 1

This is called "a motion". Even though linewise motions result in a line range.

Normally, it's enough to do 5J and there's no need for "join" operator. However, if you really want it, you can make use of :h g@ and :h 'opfunc' A simplified example:

" very basic "join" operator
nnoremap <silent>J :set opfunc=OperJoin<CR>g@
function! OperJoin(type) abort
    '[,']join
endfunction

Now Ja{ will do the job.

Answer 2

Well, since J works in visual mode...

va{J

More generally v[motion or text object]J. Normally I would say this is a bit of an anti-pattern (prefer [operator][motion or text object]), but there is no join operator.

Here, even v%J should work

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Alternately, use :join, which takes a range, and ranges can be quite powerful:

.,/}/join

Answer 3

The commandline command you're looking for is 'j':

:1,5j