state_machine寶石如何使用transition_for

Question

我想用transition_for state_machine寶石但該文檔不顯示哪一個對象，我應該使用：

http://rdoc.info/github/pluginaweek/state_machine/master/StateMachine/Event:transition_for

你有一個例子來告訴我？

Answer 1

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如果你想要做的是防止自己意外觸發，將拋出一個異常（不是試圖去查看所有活動更窄的範圍內）的事件，那麼你也可以做到這一點...

stately = Stately.new 
stately.state 
#=> :pending 

stately.can_approve? 
#=> true 
stately.can_decline? 
#=> true 

stately.approve 
stately.can_approve? 
#=> false 
stately.can_decline? 
#=> true