C++11 and Boost - Succinct like Python

Re:C++11 and Boost - Succinct like Python by danking00 on Wednesday October 31, 2012 @08:29PM (#4725571)

Your example,

    void foo() {
      auto items = {1,2,3,4};
      return;
    }

is the case of poorly designed syntax, in a truly Hindley-Milner system there is no expression which doesn't have a type. Now, we could add some syntax that screws that up, say:

    let v = I-HAVE-AN-AMBIGUOUS-TYPE in 0

But that's rather silly, isn't it? If a value isn't used then I would, personally, like my language to optimize it away. So why not ditch such silly syntax?

This is part of why I said that the foundations of C++ are too far-gone.

And this syntax isn't necessary to save on typing. In a language that supported syntactic macros (such as Scheme or Racket) we could write something like:

   auto items = my-vector-syntax(1,2,3,4);

which expands to something like:

    auto items;
    items.push_back(1);
    items.push_back(2);
    items.push_back(3);
    items.push_back(4);

If you're interested in true syntactic macros for non-sexp languages (though I do suggest getting over the parentheses, my color settings make them nearly indistinguishable from the background) look at Rust [1].

Actually, Rust also has type inference [2].

Hell, stop programming in C++ and start using Rust! [3]

[1] http://dl.rust-lang.org/doc/tutorial-macros.html [2] http://dl.rust-lang.org/doc/0.4/rust.html#type-system [3] http://www.rust-lang.org/

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Re:C++11 and Boost - Succinct like Python by fusiongyro on Wednesday October 31, 2012 @09:05PM (#4725677)

Having programmed Haskell for the last seven years (and C++ for zero) I have a fairly decent handle on what HM is all about. If all you had said is that the foundations of C++ are too far gone, there wouldn't be anything to discuss. But the foundations of C++ being what they are, there's no point being offended when unfixable things go unfixed. I love HM, but you can't just throw it in any old language simply because it's cool. The language's semantics need to allow for it, and they just don't with C++.

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Re:C++11 and Boost - Succinct like Python by danking00 on Thursday November 01, 2012 @06:34AM (#4726905)

Correct, I do not suggest adding HM to C++.

I suggest using a HM language when you start a new project.

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Re:C++11 and Boost - Succinct like Python by comex on Thursday November 01, 2012 @02:09PM (#4728848)

It's possible to do exactly that (a function that initialized a vector with its arguments) in C++ with variadic templates...

You might end up in trouble if you did something like

    auto v = vec(
                  vec(1.2, 3.4),
                  vec(0)
                )

not sure how well other languages deal with that.

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Re:C++11 and Boost - Succinct like Python by daivd on Thursday November 01, 2012 @06:11AM (#4726857)

"Hell, stop programming in C++ and start using Rust!" I plan to try to do that, when Rust has become more stable.

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Re:C++11 and Boost - Succinct like Python by kibwen on Friday November 02, 2012 @01:46PM (#4733833)

No need to downvote this; I'm an enthusiastic Rust follower and I as well recommend that you stay far away from Rust until it settles down a bit. Wait for 0.5 if you're adventurous, 0.6 if you expect some degree of feature-completion, 0.7 if you're fine with half-finished standard libraries, and even later if you expect a high degree of stability, ergonomics, documentation, or performance.

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