Adding leading and trailing space when entering insert mode

Question

I use vim with ruby. I have a habit of opening and closing brackets when I define new function or a block.

For example I would type:

array.map {}_ # _ - cursor position after finishing typing

So I am still in Insert mode I have a mapping imap jk <esc> to get me out to normal mode. Cursor is going back under the closing bracket and I can press i to start typing inside the brackets.

My question is how would I go around creating the mapping <leader>i that would insert spaces automatically on both sides of the cursor?

array.map {}_ # jk<leader>i
array.map { _ }

Answer 1

I think, instead of:

array.map { _ }

It would be better to have:

array.map { _}

That is, the cursor is on the second space. Then, whatever you'd type would have a space after it. And a mapping for that would look like:

nnoremap <leader>i i  <esc>i

• i, followed by two spaces
• an <esc> to go back to normal, at which point the cursor would be on the second space,
• another i to go back to insert mode.

If you have arrow keys working in insert mode, you could use this:

nnoremap <leader>i i  <left>

Answer 2

You could simply do:

inoremap <leader>i i<space><space><left>