On Thursday, 11 April 2013 at 09:27:11 UTC, kenji hara wrote:
No. In this case, it is the purpose of 'scope ref', not is the
implementation details.
What is the language semantics and what is the implementation
detail - that
varies depending on what is properly supported in the language.
D
explicitly distinguishes lvalues and rvalues, and also defines
that rvalue
cannot be taken its address (== reference).
The purpose of 'scope ref' is that the parameter can be
received both
lvalues and rvalues with one function body. To receive lvalues,
scope ref
should take the address of them. As a conclusion, to receive
rvalues
temporary creation is necessary in caller site.
Yes, it mostly represents implementation details, but it is
still
description of language semantics.
This confusion is almost inevitable. Because the essential
purpose of
'scope ref' is already "efficiency".
Furthermore, note that the desired "efficiency" is not "the
speed of
argument passing".
I recognize that it is "to avoid code bloating of function
body". If you
need "most efficient argument passing", you should choose it
from the
argument type. 'scope ref' is not a thing to make the choice
automatic.
Kenji Hara
I trust your judgement then, will update DIP then. But I am still
afraid of confusion.
