Module:Yesno

Documentation for this module may be created at Module:Yesno/doc

-- Function allowing for consistent treatment of boolean-like wikitext input.
-- It works similarly to the template {{yesno}}.

return function (val, default)
        -- If your wiki uses non-ascii characters for any of "yes", "no", etc., you
        -- should replace "val:lower()" with "mw.ustring.lower(val)" in the
        -- following line.
        val = type(val) == 'string' and val:lower() or val
        if val == nil then
                return nil
        elseif val == true 
                or val == 'yes'
                or val == 'y'
                or val == 'true'
                or val == 't'
                or tonumber(val) == 1
        then
                return true
        elseif val == false
                or val == 'no'
                or val == 'n'
                or val == 'false'
                or val == 'f'
                or tonumber(val) == 0
        then
                return false
        else
                return default
        end
end