修time_short函数一个错误

Zframework/stringExtend.lua

@@ -131,9 +131,8 @@ function STRING.time_short(t)
     -- floor seconds
     timeUnits[#timeUnits]=floorint(timeUnits[#timeUnits])
 
-    local outputStr=''
     for i=1,#timeUnits do
-        if timeUnits>0 then
+        if timeUnits[i]>0 then
             return timeUnits[i]..timeLetters[i]..' '..timeUnits[i+1]..timeLetters[i+1]
         end
     end