That clears things up completely. Thanks for the help, everybody!
On Monday, April 22, 2013 10:48:11 PM UTC-4, tbc++ wrote:
To simplify the problem:
((binding [*funkybind* true]
(fn [] *funkybind*)))
This is the same problem as your lazy-seq example. The issue is that
*funky-bind* is
I've encountered a situation where the binding function doesn't work as I
expect it:
user (def ^:dynamic *funkybind* false)
;; expected
user (binding [*funkybind* true]
*funkybind*)
true
;;expected
(binding [*funkybind* true]
((fn [] *funkybind*)))
true
;;... huh?
(binding [*funkybind*
Hi Daniel
map is creating a lazy seq, which isn't evaluated until the REPL's
forces it to be printed, which is outside the scope of the binding.
This:
(binding [*funkybind* true]
(doall (map (fn [_] *funkybind*) [1 2])))
forces evaluation inside the binding, and does what you want.
This is
If you want to capture the binding and have laziness together you can also
use `bound-fn`.
(binding [*funkybind* true] (map (fn [_] *funkybind*) [0 1]))
;= (false false)
(binding [*funkybind* true] (map (bound-fn [_] *funkybind*) [0 1]))
;= (true true)
On Tue, Apr 23, 2013 at 11:52 AM, Travis
To simplify the problem:
((binding [*funkybind* true]
(fn [] *funkybind*)))
This is the same problem as your lazy-seq example. The issue is that
*funky-bind* is not deref'ed when the anonymous fn is created, but when it
is executed. In this example, by the time the fn is executed, *funkybind*
