On 11/11/2013 05:47 PM, Dicebot wrote:
On Monday, 11 November 2013 at 16:28:17 UTC, Timon Gehr wrote:
I don't agree. (The argument against implicit mixin features was a
complete lack of hygiene, not the mere possibility of accessing the
caller scope.)
How would you expect it to be hygienic in any way if it has implicit
outer scope access? Reasoning is pretty much the same as with mixins.
With mixins _every_ identifier is by _default_ inserted/looked up in the
so-called 'outer scope', whereas declarations and normal symbol lookups
within macros are hygienic by default. Macros are as much about
reflection as about code generation. The trade-offs are simly not the
same. Implicit outer scope access does not imply it behaves in a
counter-intuitive manner. (It could just reflect some debug information
after all, or perform some additional checks on the context for more
safety, etc.) I will be really unhappy with any proposal that does not
allow to interchange function calls with macro calls transparently, even
though such a scheme allows more abusive code to be written as well. If
in some code base macros should be clearly marked, a naming convention
(eg. prefix macro names with 'macro') can be used. (Enforcing such a
convention is trivial and amounts to eg. a few lines of additional code
in a modified D front end.)
