On 30 January 2013 23:32, Chas Emerick <c...@cemerick.com> wrote: > On Jan 30, 2013, at 12:23 PM, Michael Fogus wrote: > >>> RuntimeException EvalReader not allowed when *read-eval* is false. >> >> The problem is that the second eval gets (<the actual + function> 1 2 >> 3) which invokes the right pathway triggering the exception. You can >> trigger the same exception by: >> >> (binding [*read-eval* false] (eval (list + 1 2 3))) > > Re-reading this, I'm clearly not grokking something here. Maybe I'm having a > slow afternoon; send help. :-P > > This obviously ends up running through EvalReader — but why? How is > LispReader ever involved at all?
I believe the story goes like so: The eval call here compiles a list of a function object and three numbers. The function object gets compiled to code which effectively calls readString on "#=(clojure.core$_PLUS_. )". (It so happens that print-dup knows how to handle functions; if it didn't, an exception would be thrown during compilation with the message "Can't embed object in code, maybe print-dup not defined: ...".) When the compiled code is executed, readString gets called to reconstruct the function, and since *read-eval* is false, this fails. +1 to setting *read-eval* to false by default, by the way. Cheers, Michał > > Thanks, > > - Chas > > -- > -- > 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. > > -- -- 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.
