Here's a bit more, public domain as usual:
(defn get-ultimate-cause [exception]
(loop [e exception]
(let [e2 (. e getCause)]
(if-not e2
e
(recur e2)))))
(defmacro with-stack-trace [& body]
`(try (eval (quote (do ~...@body)))
(catch Throwable ex#
(. (get-ultimate-cause ex#) printStackTrace))))
Improved with-stack-trace. I got an exception with causes stacked four
deep, which printed at the repl with the final one ending "... 7 more"
and the line number in my own code that set it off buried in the
elided portion, so I decided to hell with those really deeply nested
exceptions Clojure tends to churn out. The get-ultimate-cause fn gets
the exception at the root of the cause chain, and with-stack-trace now
uses it.
(defn map-preserve-raw [f coll keys?]
(if (map? coll)
(loop [m {} s coll]
(if (empty? s)
m
(let [e (first s) k (first e) v (second e)]
(recur (assoc m (if keys? (apply f [k]) k) (apply f [v]))
(rest s)))))
(let [x (map f coll)]
(if (vector? coll)
(vec x)
(if (set? coll)
(set x)
x)))))
(defn map-preserve [f coll]
(map-preserve-raw f coll false))
(defn map-code [f coll]
(map-preserve-raw f coll true))
user=>(map-preserve #(* 2 %) {:key1 3 :key2 17 :key3 1/2})
{:key3 1, :key2 34, :key1 6}
Now one version map-preserve for transforming data and one map-code
for transforming code for macro purposes.
I should make the latter recursive.
Done.
(defn map-code [f code]
(if (coll? code)
(map-preserve-raw #(map-code f %) code true)
(apply f [code])))
This makes with-derefs (part of super-lazy-seq) simpler:
(defn with-derefs [names code]
(map-code #(if (and (symbol? %) (contains? names %))
(list 'deref %)
%) code))
Tested, works.
This new with-derefs is very clear: map-code if symbol in names deref
it otherwise don't touch it. Abstracting this stuff helps readability,
not just productivity.
In fact ...
(defn map-recursive-raw [f obj keys?]
(if (coll? obj)
(map-preserve-raw #(map-recursive-raw f % keys?) obj keys?)
(apply f [obj])))
(defn map-recursive [f coll]
(map-recursive-raw f coll false))
(defn map-code [f code]
(map-recursive-raw f code true))
OK, I'm really done this time. I promise.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to [email protected]
Note that posts from new members are moderated - please be patient with your
first post.
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
-~----------~----~----~----~------~----~------~--~---
