Re: [RFC] Convert builin-mailinfo.c to use The Better String Library.

> A canonical example is that of a loop. Consider a simple C loop over
> an array:
>
> void foo(int array[10])
> {
>     for (int i = 0; i < 10; i++)
>     {   int value = array[i];
>         ... do something ...
>     }
> }
>
> It's simple, but it has a lot of problems:
>
> 1) i should be size_t, not int

>
> Since this thread is talking about C++, let's look at the C++ version:
>
> void foo(std::vector<int> array)
> {
>   for (std::vector<int>::const_iterator
>        i = array.begin();
>        i != array.end();
>        i++)
>   {
>     int value = *i;
>     ... do something ...
>   }
> }

> Frankly, I don't want to write loops that way. I want to write them
> like this:
>
> void foo(int[] array)
> {
>   foreach (value; array)
>   {
>     ... do something ...
>   }
> }
>
> As a programmer, I'm specifying exactly what I want to happen without
> much extra puffery. It's less typing, simpler, and more resistant to
> bugs.
>
> 1) correct loop index type is selected based on the type of array
> 2) arrays carry with them their dimension, so foreach is guaranteed to
> step through the loop the correct number of times
> 3) implementation decides if pointers will do a better job than
> indices, based on the compilation target
> 4) type of value is inferred automatically from the type of array, so
> no worries if the type changes
> 5) Null arrays have 0 length, so no crashing
> 6) works with any collection type