On 13-04-12 07:47 AM, Diggory Hardy wrote:
Hello list (new here),
May I comment on a post from this Monday?
Sure. But I ought to point out: we're in a "stabilizing and finalizing"
phase with the language now -- picking through corner cases and
remaining internal contradictions. Broad reorganization of assignment,
equality and argument-passing is out of scope at this point. These ships
sailed a year or two ago.
I agree with the majority on the list that requiring use of the ampersand when
calling is a useful feature, but why not automatic dereferencing everywhere?
There are two problems with this, namely comparison and assignment.
We auto-dereference on . (dot) already since it can't be overridden;
most other operators we allow overriding, and those have the option of
dereferencing when applied to pointers. Many do.
For the former, I think D really got it right with `x is y` to compare
references and `x == y` to compare objects/boxes. In the case of references to
references (e.g. ~@int) it would have to be decided which references were
compared by "is", but in any case "&" can be used to get a reference to
compare.
There are plenty of strategies for comparing. We permit overriding
operator == for this reason. Adding another operator like 'is' doesn't
seem like it'll make things more clear (memories of eq? eqv? and equal?
from lisp). I'd prefer adding a PtrEq trait with .ptr_eq() for @, ~ and
& types.
Second thing: why are semicolons required at the end of lines at all? Go,
Scala etc. manage fine without.
Most such rules wind up either whitespace sensitive or requiring a bunch
of lookahead. We don't want either of those. This is a major bikeshed
that _everyone_ has an opinion on; absent a syntactic ambiguity or error
in our existing rules, we're going to leave it alone.
-Graydon
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