On Fri, Jun 26, 2009 at 9:22 AM, Michele Simionato<michele.simion...@gmail.com> wrote: > > On Jun 26, 9:53 am, Michele Simionato <michele.simion...@gmail.com> > wrote: >> I want to asset the status of Clojure >> macros with respect to hygiene. > > Some further experiment: > > $ clj > Clojure 1.1.0-alpha-SNAPSHOT > user=> (def x 42) > #'user/x > user=> (defmacro m[] 'x) > #'user/m > user=> (m) > 42 > user=> (let [x 43] (m)) > 43 > > There is no referential transparency, it seems.
How not? > Also, it looks like > Clojure macros are runtime macros, > i.e. they may depend from runtime values and macro expansion cannot be > performed statically > without running the program (which is usually considered pretty bad). > Am I correct? No. Please use macroexpand in order to facilitate yourunderstanding. By using quote, and not syntax-quote, you have written an intentionally capturing macro: user=> (def x 42) #'user/x user=> (defmacro m[] 'x) #'user/m user=> (macroexpand '(m)) x user=> (let [x 43] (m)) ;i.e. (let [x 43] x) 43 The correct way is to use syntax-quote: user=> (defmacro m[] `x) #'user/m user=> (macroexpand '(m)) user/x user=> (let [x 43] (m)) ;i.e. (let [x 43] user/x) 42 > Finally, as an unrelated question, is there an equivalent of macrolet > in Clojure? Not yet. Rich --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
