Creating Vim binding for checkbox using regex for lua configuration

So I have todo list in my vim notes and I wanted to create vim bindings to create checkbox ,close checkbox,open checkbox.I found a article by marcelfischer which had a similar requirement.He had used regex to do so.I decided to do the same for my lua configuration.

Requirement

If there is item with * then we need to add a checkbox

* todo item 1
*

will change into

* [ ]todo item 1
* [ ]

If there is checkbox we should be able to close the same

* [x]todo item 1
* [x]

Also we should be able to open the closed checkboxes

Regex for identifying the pattern

So the regex to identify * or * [ ] or * [x]will be as below

\*\s(\[\s\]|\[x\]|)*

and to identify closed checkbox will be

\*\s(\[x\]|)*

Vim substitute command

To create the vim key bindings for our requirement we will using the vim substitute command for single line

:s/pattern/text/

Here the pattern will be the regex for the pattern.So two commands will be

:s/\v\*\s(\[\s\]|\[x\]|)*/* [ ]/

Here we added an extra \v in the regex.This to handle groups () in regex in vim.Check out this stack overflow question for more details.

Keybindings in vim lua configuration

So next I created two vim keybindings for lua configuration.

To create or open checkbox

vim.api.nvim_set_keymap('n', '<Leader>to',':s/\\v\\*\\s(\\[\\s\\]|\\[x\\]|)/* [ ]/<CR>',
{ noremap = true, silent = true })

To close checkbox

vim.api.nvim_set_keymap('n', '<Leader>tc',':s/\\v\\*(\\s\\[\\s\\])/* [x]/<CR>',
{ noremap = true, silent = true })

Here you can see we have added a extra escape character \ to the regex.This is because lua parser will give error for escape character for regex.Checkout more details in the stack overflow question.

You can find the youtube video for the above steps below