Completion su mode in lua

completion_submodes.lua

------ Completion ^X submode mappings
M._my_completion_mappings = function ()
    --@note: Function that sets mappings to workaround completeopt="noselect"
    --this allows for actually selecting the first entry when using <C-x>
    --submodes, and therefore easier chaining <C-x><C-n> brcomes
    --<C-x><C-n><C-n>
    if string.match(vim.o.completeopt, "noselect") == nil then return end
    local modes= {"l", "n", "k", "t", "i", "]", "f", "d", "v", "u", "o", "s", "p"}
    for _, mode in pairs(modes) do
        local map = string.format("<C-x><C-%s>", mode)
        local remap = string.format("<C-x><C-%s><C-%s>", mode, mode)
        gmap('i', map, remap, opts)
    end
end