Fun with templates

[Tommi]

On Sunday, 7 July 2013 at 17:48:17 UTC, Dicebot wrote:
> On Saturday, 6 July 2013 at 18:54:16 UTC, TommiT wrote:
>> He's talking about changing the semantics only on POD types, 
>> like int, struct of ints, static array of ints... only types 
>> that can implicitly convert from immutable to mutable.
>
> Than it does not really solve anything. Have you measured how 
> much template bloat comes from common meta-programming tools 
> like std.algorithm and how much - from extra instances for 
> qualified POD types? It is better to solve broad problem 
> instead and get this special case for free, not add more 
> special cases in a desperate attempts to contain it.

Basically all I know about the performance issue being discussed 
here is that: "Code bloat is bad, m'kay". But note that Artur's 
suggestion would also change language semantics to a more 
sensible and convenient default. For example:

void foo(T)(T value)
if (isIntegral!T)
{
    value = 42;
}

...I can feel free to mutate 'value' without having to worry 
about somebody breaking my function by calling it with an 
argument of type like const(int), immutable(short), shared(long) 
...