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Re: a style question:

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On 31/08/2015 16:46, Melzzzzz wrote:
> On Mon, 31 Aug 2015 11:50:50 +0100
> Bartc <bc@freeuk.com> wrote:

>> On 31/08/2015 11:24, Malcolm McLean wrote:

>>> Usr::Graphics::BezierPathSimple<Math::real64_t, GREEN>

>> What a language! (If C++ had never
>> been invented, and someone presented something like this, we'd all
>> think it was a wind-up.)
>>
>
> Take a look at this expressive power, how many lines of code you need in C for this:
>
> #include <iostream>
> #include <vector>
> #include <list>
> #include <string>
> #include <type_traits>
>
> namespace mine {
> 	using std::begin;
> 	using std::end;
> 	template <class T>
> 	decltype(begin(std::declval<T&>()),
> 		end(std::declval<T&>()),
> 		std::true_type{})
> 	is_container(int);
> 	template <class T>
> 	std::false_type is_container(...);
> };
>
> template <class T>
> using is_container = decltype(mine::is_container<T>(0));
>
> template <class T>
> void print(const T& cnt,std::true_type)
> {
> 	for(auto i:cnt)std::cout<<i<<'\n';
> }
>
> template <class T>
> void print(const T& cnt,std::false_type)
> {
> 	std::cout<<cnt<<'\n';
> }
>
> void print(){}
>
> template <class K,class ...T>
> void print(const K&k, const T&...t)
> {
> 	print(k,is_container<K>{});
> 	print(t...);
> }
>
> struct Prt1 {
> 	std::string prt = "famous";
> 	Prt1(){}
> 	const char* begin()const
> 	{
> 		return prt.data();
> 	}
>
> 	const char* end()const
> 	{
> 		return prt.data()+prt.size();
> 	}
>
> };
>
> struct Prt2 {
> 	int a = 5;
> 	float b = 3.4;
> 	Prt2(){}
> 	friend std::ostream& operator<<(std::ostream& os, const Prt2& p2) {
> 		os<<p2.a<<' '<<p2.b;
> 		return os;
> 	}
> };
>
> int main(){
> 	std::list<std::string> a={"a","b","c"};
> 	std::vector<float> b = {1.1,1.2};
> 	int arr[10]={0};
> 	print(a,' ',200,b,arr,Prt1{},Prt2{});
> }
>

I don't even know what you're trying to express here; I'm completely lost.

What does Prt2(){} mean inside the struct for example? What does Prt2{} 
mean inside the call to print()?

In my dynamic language, if it's just a question of printing out all 
these different kinds of data, it's very straightforward:

  a := ("a","b","c")
  b := (1.1, 1.1)
  arr := (0,)*10
  prt2 := (5,3.4)

  println a, 200, b, arr, "?",prt1

No classes, no templates, no iterators, no sub-classing, no traits, no 
'friends', no nothing. It just works. There's some support machinery in 
the background, but it's hidden away; the programmer needs to know 
nothing about it.

This could have been the same inside a supposedly more advanced language 
such as C++, but they decided to make it complicated instead!

Even if it has the capability of overriding various default behaviours, 
then sorry I'm not interested, not if it looks like the above.

The thing is, there are plenty of languages with lots of expressive 
power already built-in. And they generally have far cleaner syntax than 
C++. And they are simpler to learn. And have a quicker development 
cycle. And ... If they were all as fast as C++, who would ever want to 
use C++ again?

(BTW all these examples require me to compile them using '-std=c++11'. 
It makes you wonder what exactly C++ was capable of before 2011!)

-- 
Bartc

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Thread

a style question: G G <gdotone@gmail.com> - 2015-08-31 02:30 -0700
  Re: a style question: Ian Collins <ian-news@hotmail.com> - 2015-08-31 21:40 +1200
  Re: a style question: jt@toerring.de (Jens Thoms Toerring) - 2015-08-31 09:52 +0000
  Re: a style question: Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-08-31 03:24 -0700
    Re: a style question: Bartc <bc@freeuk.com> - 2015-08-31 11:50 +0100
      Re: a style question: Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-31 13:21 +0100
        Re: a style question: Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-08-31 05:41 -0700
        Re: a style question: Bartc <bc@freeuk.com> - 2015-08-31 14:55 +0100
          Re: a style question: Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-08-31 15:50 +0100
            Re: a style question: Bartc <bc@freeuk.com> - 2015-08-31 18:40 +0100
      Re: a style question: Melzzzzz <mel@zzzzz.com> - 2015-08-31 17:46 +0200
        Re: a style question: Bartc <bc@freeuk.com> - 2015-08-31 17:27 +0100
          Re: a style question: Melzzzzz <mel@zzzzz.com> - 2015-08-31 18:42 +0200
      Re: a style question: Jorgen Grahn <grahn+nntp@snipabacken.se> - 2015-08-31 17:41 +0000
        Re: a style question: Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-08-31 15:33 -0700
          Re: a style question: Jorgen Grahn <grahn+nntp@snipabacken.se> - 2015-09-01 08:34 +0000
      Re: a style question: Ian Collins <ian-news@hotmail.com> - 2015-09-01 07:40 +1200
        Re: a style question: Bartc <bc@freeuk.com> - 2015-08-31 21:36 +0100
          Re: a style question: Ian Collins <ian-news@hotmail.com> - 2015-09-01 08:51 +1200
            Re: a style question: Bartc <bc@freeuk.com> - 2015-08-31 22:37 +0100
              Re: a style question: Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-08-31 15:24 -0700
                Re: a style question: Ian Collins <ian-news@hotmail.com> - 2015-09-02 19:37 +1200
          Re: a style question: jt@toerring.de (Jens Thoms Toerring) - 2015-08-31 23:33 +0000
            Re: a style question: Bartc <bc@freeuk.com> - 2015-09-01 01:13 +0100
              Re: a style question: Ian Collins <ian-news@hotmail.com> - 2015-09-01 18:21 +1200
              Re: a style question: jt@toerring.de (Jens Thoms Toerring) - 2015-09-01 15:23 +0000
                Re: a style question: Bartc <bc@freeuk.com> - 2015-09-01 18:06 +0100
                Re: a style question: Jorgen Grahn <grahn+nntp@snipabacken.se> - 2015-09-01 20:39 +0000
                Re: a style question: jt@toerring.de (Jens Thoms Toerring) - 2015-09-01 20:45 +0000
                Re: a style question: Bartc <bc@freeuk.com> - 2015-09-01 22:53 +0100
            Re: a style question: Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-08-31 17:51 -0700

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