縮短枚舉代碼

Question

什麼是在Ruby中完成此操作的簡潔方法？ 我只是想等到所有對象都在運行。這似乎太羅嗦了。

# arr contains objects that respond to running? 
all_running = false 
until all_running 
    sleep 0.5 
    all_running = true 
    arr.each{ |obj| 
     all_running = all_running and obj.running? 
    } 

end 

Answer 1

sleep 0.5 until arr.all? &:running? 

Answer 2

如何

sleep(0.5) until arr.inject(true) { |all_running, obj| all_running and obj.running? }