ruby on rails - Whats a succinct way to express 'If an array exists then do' -

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क्या निम्नलिखित को व्यक्त करने का एक अधिक संक्षिप्त तरीका है: 

  यदि Model.all array = मॉडल। सभी सरणी.ईच करें | एक | मेरे मामले में  Model.all  एक सहायक विधि है ( get_all_of_those () )। 
 
 इस दृश्य में, मैं परिणामों के आधार पर तालिका में डेटा प्रदर्शित कर रहा हूं।  a.info  हो सकता है 
 
  "div class = 'row' & gt; # {a.name} & lt; / div & gt;

आदर्श.सभी हमेशा सच्चाई है और हमेशा एक है सरणी-जैसे ऑब्जेक्ट (सख्ती से यह ActiveRecord :: रेलिंग में रिलेशंस ऑब्जेक्ट 4; रेल में एक एरे 3) आप बस ऐसा कर सकते हैं: 

  मॉडल.all.each do | a |

यदि कोई मॉडल नहीं हैं, तो लूप भी एक बार निष्पादित नहीं किया जाएगा।

(हालांकि ध्यान दें, यह कोड कुछ दिलचस्प नहीं करता है मॉडल के साथ, ताकि आपको अपने प्रश्न को इस प्रकार अपडेट करने की आवश्यकता हो: आप अंतिम परिणाम क्या चाहते हैं? एक मौका है कि आप Model.pluck (: info) )

की तलाश में हैं

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