I see. This is honestly something I hadn't considered, but since Riddley actually uses the Clojure compiler internals to track locals, this would be as simple as a (when-not (contains? (riddley.compiler/locals) (first expr)) ...) guard in the macroexpansion. As Ben points out, using the compiler this way is the only way to make sure that locals are consistent everywhere, rather than just in your own targeted use to track shadowing.
Hope that helps, Zach On Tue, Sep 3, 2013 at 12:41 PM, Konrad Hinsen < googlegro...@khinsen.fastmail.net> wrote: > --On 3 septembre 2013 02:08:23 -0700 Zach Tellman <ztell...@gmail.com> > wrote: > > Hey Konrad, you can maybe speak with more authority as to what >> tools.macro does and doesn't provide, but my reading of it is that it >> does expression walking to prevent bound variables from being incorrectly >> symbol-macroexpanded. This seems only important in the context of >> symbol macros, however; if you don't use symbol macros it's functionally >> equivalent to clojure.walk/macroexpand-all. >> > > Not quite. It expands only terms that are evaluated, using a built-in > table of special forms, and it allows local macro definitions (macrolet). > But most importantly, it tracks local bindings and expands only macros that > are not shadowed. So if you have > > (defmacro foo [] ...) > (let [foo (fn [] ...)] > (foo 'bar)) > > the form (foo 'bar) is not expanded because its local binding is a > function. The version in clojure.walk doesn't take this into account, and > can therefore produce incorrect code, which is a major pain to debug. I > know because it happened to me, that's why I ended up writing my own macro > expander. And that's why I wonder how riddley handled this. > > > Konrad. > > -- > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscribe@**googlegroups.com<clojure%2bunsubscr...@googlegroups.com> > For more options, visit this group at > http://groups.google.com/**group/clojure?hl=en<http://groups.google.com/group/clojure?hl=en> > --- You received this message because you are subscribed to a topic in the > Google Groups "Clojure" group. > To unsubscribe from this topic, visit https://groups.google.com/d/** > topic/clojure/a68aThpvP4o/**unsubscribe<https://groups.google.com/d/topic/clojure/a68aThpvP4o/unsubscribe> > . > To unsubscribe from this group and all its topics, send an email to > clojure+unsubscribe@**googlegroups.com<clojure%2bunsubscr...@googlegroups.com> > . > For more options, visit > https://groups.google.com/**groups/opt_out<https://groups.google.com/groups/opt_out> > . > -- -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
