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0 pointsAnimalMuppet10y ago0 comments

> > sometimes completely at odds with the way other languages use them: e.g. C++ also has functors, and they're completely unrelated to Haskell functors.

> Really, this should be considered as C++ perverting the existing terminology from category-theory for Functors.

Only if you assume that category theory is the correct source of meaning of such terminology. But Wikipedia, for example, lists functor as being ambiguous - there's the category theory version, and there's the programming version, which is a function object. It lists a bunch of languages (C++, C#, D, Eiffel, Java, JavaScript, Scheme, Lisp, ObjectiveC, Perl, PHP, PowerShell, Python, and Ruby) that support some variant on this theme. It seems rather arrogant to say that the category theory definition is the one that should be the one we mean when discussing a programming language, rather than the one used by a large number of programming languages.

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semigroupoid10y ago

The definition of functor in category theory is from 1945 while most of today's mainstream programming languages are much younger than that. The people who wrote those definitions for C++, C#... simply ignored the existing terminology.

AnimalMuppetOP10y ago

Fair enough. And yet, at the time (and even today, outside of the FP crowd), category theory is really far outside the scope of what most people consider programming, so it's hard to blame them for not looking there for terms.

For that matter, category theory borrowed the word from linguistics, and most definitely did not keep the same meaning.

sordina10y ago

I certainly wouldn't blame anyone for not being familiar with the terms. What I would blame people for is attacking Haskell's choice of terminology due to it not 'being like c++'. A generous interpretation of intent goes a long way, and if that is out of reach, at least do enough research to make sure you're not pointing out weaknesses based on a false premiss. Instead I commonly see people starting from "I don't find Haskell intuitive" and extrapolating to "Haskell's contributors are indoctrinated and people who defend its use of established terminology are arrogant". Maybe I should just ignore such points of view but they seem to be infectious.

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