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val filesHere = (new java.io.File(".")).listFiles
val filesHere2 = (new java.io.File(".")).listFiles
scala> filesHere == filesHere2
res0: Boolean = false
That is quite counter intuitive. I would rather expect that filesHere and filesHere2 are equal.
This is certainly due to a semantics mismatch between Java and Scala, e.g., about arrays or (files) equality. Clearly, I am missing something here!
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But in Scala, == is testing for value equality. Let's understand with example. Example : Scala.
== is a final method, and calls . equals , which is not final. This is radically different than Java, where == is an operator rather than a method and strictly compares reference equality for objects.
If I ruled the world, I would deprecate Scala's eq method on the grounds that the name is extremely confusible with equals and ==. Instead English does have a word which expresses identity as opposed to equality: I would simply call it is .
Similarly I would replace Scala's ne (which is a terrible name, since it's both an abbreviation and incomprehensible) with isnt .
Seems to me these could actually be added to AnyRef and the old methods deprecated, even at this late stage.
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