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by groby_b 719 days ago
Or any other major commercially used language right now?

Look, I'm glad you work in a language where you don't need to describe those things any more, but the vast majority of people still do. And for that group of people, understanding that "Design Patterns" is a dictionary, not a recipe book, is a really important thing.
1 comments
qsort 719 days ago
What modern version of a "commercially used language" needs patterns a la GoF? Most of them simply disappear as the language is made more expressive than the horror that was pre-standard C++. Modern Java or C# are not at all like that.

It's not a bad book if you read it as positive account rather than a normative prescription, I have the dead tree version on my bookshelf, but it's also a narrow, historically-informed perspective. Nothing about patterns is a fundamental concept that persists across languages (or even time), unlike things like SICP, algorithms, CS concepts, etc.

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layer8 719 days ago
How are (for example) Adapter and Proxy not fundamental patterns applicable in most programming languages? Many people take them for granted today and maybe don’t think about them as design patterns, and a modern description will use different examples than the GoF book, but they are patterns nonetheless, and the GoF book contributed a lot to them having universally agreed and well-recognized names.
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qsort 719 days ago
Neither of them is a fundamental idea about programming in general, unless the only languages we are considering are Java, C#, and Python spoken with a thick Java accent.

Adapter is an OOP-ism. If you take, for example, any ML-family language, you won't find anything of the sort. Even staying in OOP-land, in a language where inheritance goes on the prototypal chain, you wouldn't solve the problem like that.

Proxy is a more general concept, but the way it's described in GoF is still tied to a class/interface/implementation mechanism. In other languages it would often just be a function. I don't know what overarching lesson you would draw from it except "write code to do things".

As I said I don't think it's a bad book, it's definitely something you should read, even just for the meta-level language it (successfully!) introduced. Where I differ is that I don't believe the book is quite as successful at transcending the "traditional" OOP mechanisms. It's mostly "how to accomplish things in Java 1.5".

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layer8 719 days ago
> Adapter is an OOP-ism. If you take, for example, any ML-family language, you won't find anything of the sort.

This is incorrect. For example in SML you have signatures and structures, which are roughly analogous to interfaces and implementing classes in OOP. And SML functors are adapters that can adapt a structure of one signature to a different signature. Or they may create a proxy structure for a given structure. Furthermore, you could easily imagine a derived language where functors are just regular functions and structures are regular values.

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qsort 719 days ago
I would argue that ML functors are significantly more general than Adapter as presented in Design Patterns, the transferable "big idea" being the underlying type theory (functors as high-kindered types) as opposed to the pattern.

> you could easily imagine a derived language where functors are just regular functions and structures are regular values

I'm pretty sure someone taught me this some time ago but I have forgotten it, can you do it that easily? Aren't you at least supposed to make a distinction about types and kinds? I really don't remember, I'm genuinely asking.

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groby_b 719 days ago
These are still relevant even in modern Java or C# or C++. Just because the language can express things in a more modern way doesn't mean you always will. Or should. Or can.

And I agree that it's a historically informed perspective. But guess how much code is modern code versus historic^W legacy code. Nobody is arguing (well, at least I'm not) it's a foundation of CS. Nor is any reasonable person arguing it's a normative prescription - see the comment about "not a recipe book".

It's the equivalent of a dictionary/thesaurus for a writer - necessary, but not world-changing. Always has been. Still is.

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