On 09/15/2011 06:01 PM, Jonathan M Davis wrote:
On Thursday, September 15, 2011 14:59:29 Don wrote:
On 08.09.2011 17:26, Christian Kamm wrote:
Timon Gehr wrote:
I am strongly in favor of disallowing any cases where mixin
declarations
shadow declarations that were used to compute mixin declarations in a
scope that allows forward references.
Any thoughts on this?
Order-of-static-evaluation problems are not limited to mixins:
static if (!is(typeof(foo)) enum bar = 1;
static if (!is(typeof(bar)) enum foo = 1;
with the way dmd handles forward references, this can go either way
depending on which static if gets evaluated first. D's wish that 'the
order of declarations does not matter' is impossible to fulfill due to
mixins and static if.
They are special because they can alter the symbol table based on the
contents of the symbol table.
I think you could get away with defining that 'the order of declarations
does not matter - except for static if and mixin which always get
evaluated in lexical order'. I'm not sure how much work it'd be to make
dmd behave that way. It probably wouldn't be worthwile.
I prefer: The order of declarations NEVER matters, and the above code is
illegal. It's easy to implement.
The order matters for static if and version when you have else-if and/or else
branches for them - it would be a problem if it didn't (especially for
version, which is so dead-simple), but aside from that I agree that the order
of declarations in non-local scope should never matter.
- Jonathan M Davis
I'd go as far as saying that even in local scopes, local functions
should be able to forward-reference other local functions. Currently,
you cannot even insert forward declarations for local functions.
