Operator overloading -- lets collect some use cases

[Yigal Chripun]

Jarrett Billingsley wrote:
> On Sun, Dec 28, 2008 at 11:50 AM, Don<nospam at nospam.com>  wrote:
>
>> So, please post any use cases which you consider convincing.
>
> Virtually all I use it for is making containers.  I do almost no
> numerical programming.  I would probably not miss much if all I could
> overload were opIndex[Assign], opSlice[Assign], opCat[Assign], and
> opApply.
>
> As you've noted before, overloading of the arithmetic operators isn't
> useful when you only have access to two operands.  It seems like an
> AST transformation (macros!) on mathematical transformations into
> possibly-compound operations would be much more useful than plain old
> operator overloading.  We're already forced to use expression
> templates to do anything useful with operator overloading; why not put
> a more general, efficient, concise form of that in the language
> itself?

could you please elaborate on this, and/or provide a code example?

Also, just wanted to mention that other languages provide similar 
concepts but with slightly different mechanisms - for example, scala 
allows to declare a function with two parameters as an infix function, 
this idea is also present in functional languages like ML. So my 
question therefore is:
what are the pros/cons of limiting this to already existing operators in 
the language (similar to C++) vs. allow any kind of symbol and/or 
function name?

Downs uses his famous operand1 /func/ operand2 pattern, for example with 
a map function. Should D support this in the language?