Thank you for the quick answers. I'm new to clojure and functional
programming so this "lazy"-stuff is new to me, but it makes sense and
is really cool.
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups
"Clojure" group.
Map is lazy. You are presumably executing (foo) at the REPL. In the
first foo, since the value calculated by map is unused, no elements of
the seq are calculated and your anonymous function never runs. In the
second foo, since the function actually returns the value and the REPL
wants to print it,
First, "map" returns a lazy seq. Second, "do" only returns the result
of the last expression.
So, the mapping you do in your "do" form is never executed because you
never ask for the result.
Try wrapping the mapping in "dorun" to explicitly realize the lazy seq
from your mapping:
(defn foo []
Hi,
How come the following code does not throw an exception?
(defn foo []
(do
(map (fn [_] (throw (RuntimeException. "fail"))) [1 2])
"no exception"))
this however does throw exception:
(defn foo []
(map (fn [_] (throw (RuntimeException. "fail"))) [1 2]))
Is this a bug or am I miss
