change mixins

[retard]

Tue, 16 Feb 2010 21:08:19 +0100, grauzone wrote:

> You're discussing here about syntax proposals to make string mixins
> better readable. IMHO they should stay as ugly as they are to discourage
> using them. (Although Andrei is already fearless enough to use advertise
> string mixins as a standard way to overcome the still-too-ugly syntax
> and bad compiler optimizer support for passing delegates; the
> std.algorithm documentation still passes functions as string, and his
> book will probably too.)
> 
> Before discussing syntax improvements, you really should solve some
> basic problems of string mixins: for example, solve the issue that
> string mixins may be compiled in a completely foreign environment, as
> opposed to the environment where the user wrote them. (When I understand
> correctly, this is the "hygienic" aspect of LISP macros.)
> 
> My favorite example is still this:
> 
> void helper(int x) { /+ whatever here is +/ return x; }
> map!"helper(a)+1"(range)
> 
> Also, why should the "function" passed by the user be able to access the
> internals of std.algorithm?

Agreed, lambdas should be used instead of string macros in some cases.

> 
> Building the function with a string is not that bad (seriously ugly but
> works). What I've seen from early macro proposals didn't sound that
> great either. But what's really needed is solving the symbol lookup
> problems above. D macros were supposed to be hygienic, solving this
> particular problem.
> 
> Actually, I wouldn't be too surprised if one day, Walter announced that
> D won't get macros, because they tried to figure out how they should
> work and came to the conclusion that macros suck. That's how things work
> in D Land, right?

My guess is that macros are getting there eventually, but atm D design 
team lacks manpower and D2 release is too soon so they can't really 
introduce a half-broken macro system now.