Switch Object

local function switch_isofcase(val, values)

	local vt = type(values)

	if vt == 'table' then

		for i, v in ipairs(values) do

			if v == val then return true end

		end

		return false

	end

	if vt == 'function' then

		return values(val)

	end

	return (values == val)

end



local function switch_test(switch, val)

	for i, case in ipairs(switch.cases) do

		if switch_isofcase(val, case.value) then

			if case.func then return case.func(val, case.value) end

			return case.ret

		end

	end

	if switch.default_func then

		return switch.default_func(val, 'default')

	end

	return switch.default_ret

end



local function switch_case(switch, value, fn)

	if type(fn) == 'function' then

		table.insert(switch.cases, {value = value, func = fn})

	else

		table.insert(switch.cases, {value = value, ret = fn})

	end

end



local function switch_default(switch, fn)

	if type(fn) == 'function' then

		switch.default_func = fn

	else

		switch.default_ret = fn

	end

end



function switch()

	local s = {}

	s.cases = {}

	s.test = switch_test

	s.case = switch_case

	s.default = switch_default

	return s

end



--- Testing part ---

local fn = function(a, b) print(tostring(a) .. ' in ' .. tostring(b)) end

local casefn = function(a)

	if type(a) == 'number' then

		return (a > 10)

	end

end



local s = switch()

s:case(0, fn)

s:case({1,2,3,4}, fn)

s:case(casefn, fn)

s:case({'banana', 'kiwi', 'coconut'}, fn)

s:case({'banana', 'pineapple', 'coconut'}, fn)

s:default(fn)



s:test(0)

s:test(2)

s:test(5)

s:test(15)

s:test('kiwi')

s:test('banana')

s:test('pineapple')

s:test(nil)