max() in phobos?

[Sean Kelly]

Bill Baxter wrote:
> Is there a generic 'max' function anywhere in phobos?
> The closest I could find was std.math.fmax().

Not that works for all input types, as far as I know.  However, 
something like the code below should work.  This is off the top of my 
head so it may have bugs, but it's a general idea of what such a 
template function may need to do.

/**
  * Returns the largest of the two supplied types, or the first type if
  * the sizes are identical.  If either type is an object then both must
  * be objects of either the same type or where one is a base class of
  * the other.  Interfaces are not supported.
  */
template largestOrConvertible( T, U )
{
     static if( is( T : Object ) || is( U : Object ) )
     {
         static assert( is( T : Object ) && is( U : Object ),
                        "Types incompatible." );

         static if( T : U )
             alias T largestOrConvertible;
         else static if( U : T )
             alias U largestOrConvertible;
         else static assert( false, "Object types must be related." );
     }
     else static if( is( T : Interface ) || is( U : Interface ) )
         static assert( false, "Interface types not yet supported." );
     else static if( T.sizeof < U.sizeof )
         alias U largestOf;  // concrete type, U larger
     else alias T largestOf; // concrete type, T larger or equal
}

template max( T, U )
{
     largestOrConvertible!(T,U) max( T t, U u )
     {
         return t > u ? t : u;
     }
}

template min( T, U )
{
     largestOrConvertible!(T,U) min( T t, U u )
     {
         return t < u ? t : u;
     }
}