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by Dewie 4331 days ago
http://c2.com/cgi/wiki?AreDesignPatternsMissingLanguageFeatu...
1 comments
eru 4331 days ago
Type classes are built into the language. So they are not really `design patterns' by the original definition of the word.
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comex 4331 days ago
To be fair, most of these classes come with "laws" instances are supposed to follow, which are not encoded in the language...
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Fixnum 4331 days ago
On the other hand, the burden of proof is on the library writer who creates the typeclass instance, not on the end user - possible largely thanks to purity - whereas programmers may expect to re-implement various patterns by hand.
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eru 4331 days ago
Good point!
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Dewie 4331 days ago
That was partly my point, at least for functional languages that can express these concepts, like certain statically typed ones.
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