Clay language

[Lutger Blijdestijn]

bearophile wrote:

> Andrei:
> 
>> FWIW I just posted a response to a question asking for a comparison
>> between Clay and D2.
>> 
>> 
http://www.reddit.com/r/programming/comments/es2jx/clay_programming_language_wiki/
> 
> Just few comments:
> 
>> The docs offer very little on Clay's module system (which is rock solid
>> in D2).
> 
> D2 module system may be fixed, but currently it's not even bread-solid.
> 
> The Clay syntax for imports is more similar to what I have desired for D
> (but that () syntax is not so good):
> 
>   import foo.bar; // Imports module foo.bar as a qualified path
>   // use "foo.bar.bas" to access foo.bar member bas
>   import foo.bar as bar; // Imports module foo.bar with alias bar
>   // use "bar.bas" to access foo.bar member bas
>   import foo.bar.(bas); // Imports member bas from module foo.bar
>   // use "bas" to access foo.bar member bas
>   import foo.bar.(bas as fooBarBas) // Imports member bas with alias
>   fooBarBas import foo.bar.*; // Imports all members from module foo.bar

This looks like a subset of the D module system. The only difference is 
'static' import by default and the .* feature which has to be implemented by 
the library author in D. Are those the things you find missing in D? 
 
> I don't know about Modula3 module system, I will search info about it.
> 
> 
>>Clay mentions multiple dispatch as a major feature. Based on extensive
>>experience in the topic I believe that that's a waste of time. Modern C++
>>Design has an extensive chapter on multiple dispatch, and I can vouch next
>>to nobody uses it in the real world. Sure, it's nice to have, but its
>>actual applicability is limited to shape collision testing and a few toy
>>examples.<
> 
> I think double dispatch is enough, it cover most cases and keeps both
> compiler complexity low enough. If you put double dispatch with a nice
> syntax in D then maybe people will use it. There are many things that
> people in other languages use that C++ programmers don't use because using
> it in C++ is ugly, a pain, unsafe, etc. The visitor pattern is used enough
> in Java (Scala too was designed to solve this problem).
> 
> Bye,
> bearophile

I think I agree here. I have never programmed much in a language with 
multiple dispatch, but everytime I see dynamic casting or the visitor 
pattern in an OOP program I think about how that would be so much better. 
Honestly its just speculation, but I guess that the lack of interest is 
because it is not a widely known and available solution. Library 
implementations have issues, both usability and performance wise.