Removing from SList (std.container)...

[Tobias Pankrath]

> Can you show me an example or removing a number?

I think that is a prime example of why std.container sucks both 
in documentation and implemantation.

We really need to improve here, sadly development seems to be 
bottlenecked by Andrei working on on allocator proposal. And 
Andrei is busy at the moment.

Here is the solution. You actually need 4 different modules from 
phobos to do this and it is absolutely not obvious how to do it.

import std.algorithm;
import std.range;
import std.container;
import std.array;

void main(string[] args)
{
     SList!int list = [1,2,3,4,5]; // our list
     writeln(list.array()); // need to create an array to print 
nicely
     auto pos = find(list[], 4); // we need a range, so we search 
for the number
     auto pos2 = take(pos, 1); // but find returns a range over 
the rest, so take one
     list.linearRemove(pos2); // remove it
     writeln(list.array()); // print it
}


I needed to look it up myself and didn't find a solution on first 
try.

My first error: You can't just do find(list, 4), because an SList 
is not a range by itself. So you need opSlice (list[]) to get a 
range over list.

Then I knew already that find gives me not what I want. I somehow 
need to restrict the range pos to the first element. But how to 
do it? I wouldn't expect  a newcomer to come up with a solution 
on its own, because pos[0..1] will not work on a forward range. 
Luckily I knew std.range.takeOne.

But hold! takeOne(pos) does not work, you need take(pos, 1).

That sucks.

None of the above is stated explicitly in the documentation. I 
knew that the container generally need a range that was extracted 
from them. How should I know that in this special case a range 
from std.range will work, too? And not all ranges work, only the 
one from take.