On Monday, 31 March 2014 at 15:56:29 UTC, John Colvin wrote:
m_takeIndex = m_takeIndex++; should do exactly the same.
Nope. Nope nope nope. That's not what postfix increment is.
That's why prefix increment exists.
Yeah, it might be an odd design (dates back to poor optimising
compilers and fast INC/DEC instructions apparently), but that's
how it is in C and how it is in D, by inheritance.
I just don't see, why one would expect the assignment could come
first?!?
The post-increment has a much, much higher priority, so I would
think it is obvious that first the value is incremented and
afterwards the old value is assigned to it.
And of course, the old, non-incremented value is assigned. This
is the essence od POST incrementing - the return value of this
operator is defined to be the old value, that's the whole point
why this operator exists. (btw. I would _never_ever_ write a line
like "i++;" That's garbage. It should always be "++i;"
Yes, the optimizer will get rid of the temporary variable, but it
is absolutely unintuitive (if I read something like that my first
thought is: what is the
old value used for? Why using a temporary variable?)
But I fully agree that such a form of complicated NOP ("i =
i++;") should be forbidden or at least warned about.
