4 ms·

Certainly it does but given that Control.Monad is sufficient I do not see it as a larger issue. Haskell 2010 is a different language with libraries refactored.

by nyberg 8y ago

Certainly it does but given that Control.Monad is sufficient I do not see it as a larger issue. Haskell 2010 is a different language with libraries refactored. If you wish to use an older text (pre Haskell 2010) then it would probably be best to try either Hugs98 or one of the other haskell implementations as GHC is concerned with the current standard.

daly 8y ago
The problem is the phrase "the current standard". Is Haskell going to become the new C++? C++11, C++14, C++17, etc? Is it going to live up to the phrase "I love standards. There are so many to choose from."? Is it going to become a python 2.7 vs python 3 vs python 4 game? I understand the benefit of using the same name as you can trade on the prior mindset. But if old code won't compile then it isn't the same language. If you're going to change a language with a standard (e.g. Haskell98), change the name. Call it Peyton or something. Otherwise there will be a Haskell20 that is refactored for dependent types that won't compile under Haskell10. Then when people claim to "know haskell" the question becomes ... which language? The "current standard" game leads into "library hell".
- the_why_of_y 8y ago
  I think in theory you are correct: as soon as you have 2 different "versions" of a language, you can, with sufficient creativity, construct a program that will break with the newer version. How likely this is going to bite you in practice, though, is a different question, and one where the specifics of the language are important. C++ is a language without a module system; instead, the preprocessor resolves #include directives by textual substitution, which is of course extremely fragile wrt. compatibility, particularly considering idiomatic "header-only libraries" of the boost variety. Haskell doesn't use #include but has a module system, which avoids a lot of the C++ standard incompatibility issues, because you can compile each module independently with its required language standard. Also note that there is a pragma you can put into modules to specify the version directly inline, e.g., "{-# LANGUAGE Haskell2010 #-}" or "{-# LANGUAGE Haskell98 #-}" .

by nyberg 8y ago

daly 8y ago

The problem is the phrase "the current standard". Is Haskell going to become the new C++? C++11, C++14, C++17, etc? Is it going to live up to the phrase "I love standards. There are so many to choose from."? Is it going to become a python 2.7 vs python 3 vs python 4 game? I understand the benefit of using the same name as you can trade on the prior mindset. But if old code won't compile then it isn't the same language. If you're going to change a language with a standard (e.g. Haskell98), change the name. Call it Peyton or something. Otherwise there will be a Haskell20 that is refactored for dependent types that won't compile under Haskell10. Then when people claim to "know haskell" the question becomes ... which language? The "current standard" game leads into "library hell".

the_why_of_y 8y ago
I think in theory you are correct: as soon as you have 2 different "versions" of a language, you can, with sufficient creativity, construct a program that will break with the newer version. How likely this is going to bite you in practice, though, is a different question, and one where the specifics of the language are important. C++ is a language without a module system; instead, the preprocessor resolves #include directives by textual substitution, which is of course extremely fragile wrt. compatibility, particularly considering idiomatic "header-only libraries" of the boost variety. Haskell doesn't use #include but has a module system, which avoids a lot of the C++ standard incompatibility issues, because you can compile each module independently with its required language standard. Also note that there is a pragma you can put into modules to specify the version directly inline, e.g., "{-# LANGUAGE Haskell2010 #-}" or "{-# LANGUAGE Haskell98 #-}" .