add gs

RCCService2021/ExtraContent/LuaPackages/Packages/_Index/roblox_lua-result/lua-result/init.lua

@@ -0,0 +1,100 @@
+local Result = {}
+Result.__index = Result
+
+local ResultTypeSymbol = newproxy(true)
+
+function Result.new(status, value)
+	assert(typeof(status) == "boolean")
+
+	local result = {
+	-- Used to locate where a result was created
+		_source = debug.traceback(),
+
+	-- A tag to identify us as a result
+		[ResultTypeSymbol] = true,
+
+		_status = status,
+
+	-- The value success value or error message.
+		_value = value,
+	}
+
+	setmetatable(result, Result)
+
+	return result
+end
+
+function Result.success(value)
+	return Result.new(true, value)
+end
+
+function Result.error(value)
+	return Result.new(false, value)
+end
+
+--[[
+	Is the given object a Result instance?
+]]
+function Result.is(object)
+	if typeof(object) ~= "table" then
+		return false
+	end
+
+	return object[ResultTypeSymbol]
+end
+
+--[[
+	The given callbacks are invoked depending on that result.
+
+	Creates a new result that receives the output of the callback.
+]]
+function Result:match(successHandler, errorHandler)
+	assert(typeof(successHandler) == "function" or typeof(successHandler) == "nil",
+			string.format("Result:match expects successHandler to be a function or nil, got %s", typeof(successHandler)))
+	assert(typeof(errorHandler) == "function" or typeof(errorHandler) == "nil",
+			string.format("Result:match expects errorHandler to be a function or nil, got %s", typeof(errorHandler)))
+
+	local newResult
+	if self._status then
+		if successHandler ~= nil then
+			newResult = successHandler(self._value)
+		else
+			return self
+		end
+	else
+		if errorHandler ~= nil then
+			newResult = errorHandler(self._value)
+		else
+			return self
+		end
+	end
+	if Result.is(newResult) then
+		return newResult
+	else
+		return Result.success(newResult)
+	end
+end
+
+--[[
+	The given callback is invoked if the result is success.
+
+	Creates a new result that receives the output of the callback.
+]]
+function Result:matchSuccess(successHandler)
+	return self:match(successHandler, nil)
+end
+
+--[[
+	The given callback is invoked if the result is error.
+
+	Creates a new result that receives the output of the callback.
+]]
+function Result:matchError(errorHandler)
+	return self:match(nil, errorHandler)
+end
+
+function Result:unwrap()
+	return self._status, self._value
+end
+
+return Result