php - Why is an empty value in a shorthand if-then-else returning `true`? -

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यह बिल्कुल "समस्या" नहीं है, लेकिन एक "क्यों" सवाल है।

निम्न उदाहरण: 

  प्रतिध्वनि 'परीक्षण' (सच?: 'कुछ परीक्षण');

इस का परिणाम क्यों है: test1 इसके बावजूद कोई क्या उम्मीद कर सकता है: test ।

या दूसरे शब्दों में: null के बजाय रिक्त रिटर्न स्टेटमेंट 1 (या वास्तव में true ) क्यों है?

< P>

, टर्नरी के मध्य भाग:?: ऑपरेटर को छोड़ा जा सकता है।
foo? बार के बराबर है foo? Foo: बार । तो true?: ... हमेशा पहले true देता है।

foo? : बार "कुछ भी नहीं अगर सच" के अर्थ के साथ है और हमेशा अमान्य है, क्योंकि यह अभिव्यक्ति है कुछ वापस करने के लिए, यह अभी कुछ भी नहीं लौटा सकता है । यदि कुछ भी है, तो आप यह चाहते हैं: foo? नल: बार ।


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