[Haskell-cafe] Object Oriented programming for Functional Programmers

Gershom Bazerman gershomb at gmail.com
Wed Jan 2 23:09:03 CET 2013

On 1/2/13 4:29 PM, MigMit wrote:
>> BTW. Why you think that Eiffel type system is unsafe?
> Well, if I remember correctly, if you call some method of a certain object, and this call compiles, you can't be certain that this object actually has this method. Could be that this object belongs to some subclass which removes this method.

Eiffel doesn't handle the relationship of co- and contra-variance of 
arguments with subtyping in a principled way. This is apparently known 
as the "catcall" problem. See, e.g., this article: 


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