Why does this script not work? What do i change to fix it? Expected Identifier

RainBower = while wait() do
    script.Parent.TextColor3 = Color3.new(1,0,0)
    for i=1,15 do
        game:GetService("RunService").RenderStepped:wait()
        script.Parent.TextColor3 = Color3.new(script.Parent.TextColor3.r,script.Parent.TextColor3.g+(17/255),script.Parent.TextColor3.b)
    end
    for i=1,15 do
        game:GetService("RunService").RenderStepped:wait()
        script.Parent.TextColor3 = Color3.new(script.Parent.TextColor3.r-(17/255),script.Parent.TextColor3.g,script.Parent.TextColor3.b)
    end
    for i=1,15 do
        game:GetService("RunService").RenderStepped:wait()
        script.Parent.TextColor3 = Color3.new(script.Parent.TextColor3.r,script.Parent.TextColor3.g,script.Parent.TextColor3.b+(17/255))
    end
    for i=1,15 do
        game:GetService("RunService").RenderStepped:wait()
        script.Parent.TextColor3 = Color3.new(script.Parent.TextColor3.r,script.Parent.TextColor3.g-(17/255),script.Parent.TextColor3.b)
    end
    for i=1,15 do
        game:GetService("RunService").RenderStepped:wait()
        script.Parent.TextColor3 = Color3.new(script.Parent.TextColor3.r+(17/255),script.Parent.TextColor3.g,script.Parent.TextColor3.b)
    end
    for i=1,15 do
        game:GetService("RunService").RenderStepped:wait()
        script.Parent.TextColor3 = Color3.new(script.Parent.TextColor3.r,script.Parent.TextColor3.g,script.Parent.TextColor3.b-(17/255))
    end
end