class pair
    function __construct(public name, public value) end

    function __lt(other) return self.name < other.name end

    function __tostring() return $"\{{self.name}, {self.value}}" end
end

local pairs = {
    new pair("grass", "green"),
    new pair("snow", "white"),
    new pair("sky", "blue"),
    new pair("cherry", "red")
}

print("Before sorting:")
print("  " .. pairs:mapped(|p| -> tostring(p)):concat("\n  "))
pairs:sort()
print("\nAfter sorting:")
print("  " .. pairs:mapped(|p| -> tostring(p)):concat("\n  "))