On Wednesday, 17 December 2014 at 02:34:16 UTC, aldanor wrote:
On Wednesday, 17 December 2014 at 02:12:52 UTC, anonymous wrote:
Sure, straight forward:
mixin template makeProperty(T, string name, alias func) {
mixin("T %s() @property { return func();
}".format(name));
}
Indeed... thanks! Just one thing that I find confusing here --
how
exactly do T and func resolve when this template is mixed in?
What if there was another local symbol named "func" in the
target
scope?
As far as I understand, the string mixin is resolved first, and
then the template mixin takes place. So the progression is
somewhat like this (pseudo code):
----
mixin makeProperty!(int, "foo", f);
/* Replace "makeProperty" with its definition. */
mixin (T, name, func){mixin("T %s() @property { return
func();}".format(name));}!(int, "foo", f);
/* First round, substitute arguments for parameters. `T` and
`func` are not replaced, because they're just string contents at
this point. */
mixin (T, name, func){mixin("T %s() @property { return
func();}".format("foo"));}!(int, "foo", f);
/* Evaluate `format` and do the string mixin. */
mixin (T, name, func){T foo() @property { return func();}}!(int,
"foo", f);
/* Second round, substitute arguments for parameters. This time,
`T` and `func` are replaced. */
mixin (T, name, func){int foo() @property { return f();}}!(int,
"foo", f);
/* Didn't do any string mixins in the second round, so there's no
need for a third round. Get rid of template parameters and
arguments. */
mixin {int foo() @property { return f();}};
/* Finally, do the template mixin. */
int foo() @property { return f();}
----
Not sure if that helps or maybe it just adds to the confusion.
As to if there were `T` or `func` in the target scope, they'd be
shadowed by the template parameters, no matter if there's a
string mixin or not.
