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Breaking Change: the Hashable Class to be Removed

The Hashable class is being removed. William Hesse tells us why

Since everything is hashable, there is no need for a Hashable class. 
We've kept a class with that name alive, so that code using it wouldn't break, but now it's time to let it go.

As always, we invite you to join our Dart mailing list, ask questions on Stack Overflow, or file feature requests on


  1. Ohhh it's like IE6 + VBScript all over again.

  2. It would do dart well to be more brave with features than it has been. I think their ideals of being overly conservative may actually hurt them... who knows though? If javascript can rise to the heights it has then I think making such predictions are much harder then they seem.

  3. Fernando, how is this like VBScript? Dart is open source (VBScript wasn't), Dart compiles to JavaScript (VBScript didn't), and Dart looks like languages familiar to most developers (VBScript didn't)

    1. I think dart should be delineated by white space and it should drop the semicolons. These changes alone, would make dart seem more progressive(while it would actually be the same language). If you look around Seth, many Universities are teaching in python now. In fact, Moocs are embracing python, they have a far greater reach than brick and mortars do. I may be wrong in my assumptions, but I think that the Dart team would do well to notice this trend.

    2. University programming classrooms follow industry leaders, Python was created by open source community, adopted by industry. Is Python a good language for teaching programming is another debating issue, Java is a much better one IMHO, Dart could be once it is released.

    3. Python: Because spending two hours staring at the screen debugging a incoherent error due to a white space issue is time well spent.


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