types.lua


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--- lam.types

local types = {}

types.luatype = type

function types.lamtype (x)
	if types.luatype(x) == "string" then
		return "symbol"
	elseif types.luatype(x) == "number" then
		return "number"
	elseif getmetatable(x) and getmetatable(x).__type then
		return getmetatable(x).__type
	elseif types.luatype(x) == "table" then
		return "list"
	else
		return types.luatype(x)
	end
end

types["number?"] = function (x) return types.lamtype(x) == "number" end
types["symbol?"] = function (x) return types.lamtype(x) == "symbol" end
types["list?"] = function (x) return types.lamtype(x) == "list" end
types["procedure?"] = function (x) return types.lamtype(x) == "procedure" end
types["null?"] = function (x) return x == {} end

---
return types