Something I sometimes do for strictly personal projects:

import std.typecons : ω = tuple;
import std.typetuple : Ω = TypeTuple;

void main()
{
    auto a = 1, b = 2;
    Ω!(a, b) = ω(b, a);
    assert(a==2 && b==1);
}

On Thursday, 21 May 2015 at 19:05:16 UTC, Steven Schveighoffer wrote:
On 5/21/15 12:57 PM, Dennis Ritchie wrote:
Hi,
In Python I can write this:

if (4 <= 5 <= 6):
    print ("OK")
-----
http://rextester.com/NNAM70713

In D, I can only write this:

import std.stdio;

void main() {

    if (4 <= 5 && 5 <= 6)
        puts("OK");
}
-----
http://rextester.com/FICP83173

I wanted to ask what is the reason? Maybe the program on Python's slower
because of this? Or legacy C/C++ affected D?


There is this possibility:

switch(5){
   case 4: .. case 6:
}

You could also make some nifty abuse-of-syntax types:

struct Between(T)
{
   T low;
   T high;
bool opBinaryRight!(op : "in")(T val) { return val >= low && val <= high;}
}

auto between(T)(T low, T high) { return Between!T(low, high); }

if(5 in between(4, 6))

:)

-Steve

All this, of course, looks good, but what about the principle of the ideal programming language :)

"In the end I want to focus on one philosophical principle, which lies at the basis of my ideas about the ideal programming language. Typically, during the discussion in the forums, when you start to talk in a language that is not X features Y, be sure there is someone who will say: Why, that's if you take the features A, B and C, and screw them crutches D, E, F, then we will get almost Y. Yes, it is. But I do not like this approach. One can imagine that such programmers want some complicated way through the maze. You can go through the maze, but the way the curve and non-obvious. I also want to be instead of the labyrinth has a large area, on which from any point to any other one would go in a straight line. Just a straight line."
-----
The quotation is taken from the article:
http://habrahabr.ru/post/257875/

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