local switch = {}

switch.__index = switch

switch.__call = function(self, v)
    local c = self._callbacks[v] or self._default
    assert(c, "No case statement defined for variable, and :default is not defined")
    c()
end

function switch:case(v, f)
    self._callbacks[v] = f
    return self
end

function switch:default(f)
    self._default = f
    return self
end

return function()
    return setmetatable({
        _callbacks = {},
    }, switch)
end

-- local switch = require 'switch'

-- local numbercase = switch()
--     :case(10, function()
--         print("Hello Ten")
--     end)

--     :case(20, function()
--         print("Hello Twenty")
--     end)

--     :default(function()
--         print("Unrecognised")
--     end)
-- numbercase(15 + 5)