suggested improvements to D (Swap Operator)

[Xinok]

Warren D Smith Wrote:

> a <--> b;
> swaps a and b, same as making a tempvar t and then  t=a; a=b; b=t;
> As was pointed out by Robert W. Floyd ages ago, in his Turing award
> lecture (but nobody listened) this comes up so
> often it is worth having special syntax for it.

A few simpler symbols:
<->  I think this would work best
><  Simpler, but the developer could possibly confuse this for another symbol
::  I think this is a good symbol, except it can be confused with C's scope operator
AFAIK, D makes no use of any of these.