PHP7 Null coalesce operator

PHP7 Improved performance up to twice as fast as PHP 5.6 ,Consistent 64-bit support,Combined comparison Operator (<=>),scalar type declarations,return type declaration,null coalesce operator any many others new features.So then first see what is this operator.(??) is null coalesce operator.In previous version till 5.6 we was see a operator that is called ternary operator(?).Null coalesce operator is a new operator in php7.There has great facility for null coalesce operator which is its first operand if it exists and is not NULL; otherwise it returns its second operand.Lets see an example how to use null coalesce operator

PHP7 Null Coalesce Operator