[lua]尝试一种Case语法糖

function CaseT(arg)
    local r = arg%10

    function proxy(caller)
        caller.yield(r)
    end -- proxy

    return
        function (cond)
            if (cond == r) then return proxy end
            return function() end
        end
end

function main()
    for i=1, 10 do
        local on = CaseT(math.random(0, i))
        on(1) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(2) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(3) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(4) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(5) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(6) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(7) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(8) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(9) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
        on(0) {
          yield = function(r)
            print("CaseT.callback", i, r)
          end
        }
    end
end

main()