Re: Recursively convert Java Map to Clojure Map
Thanks for the reply. I do need to convert to java hashmaps and arraylists
because I'm trying to duplicate the testing of a clojure workflow being run
on a server thats pushing pure java context through it. So in my tests I
define a clojure map but want to javafy it to force errors to happen when I
try to evaluate the map as a function.
It's not clear to my how the postwalk-replace will work for converting
specific types (clojure maps and lists) to other types (java hashmaps and
array lists) recursively. Is the extend-protocol method discussed below not
the way to go?
On Friday, January 31, 2020 at 3:15:29 PM UTC-6, Alex Miller wrote:
>
> You don't need that - Clojure maps *are* Java maps (they implement
> java.util.Map) and you can pass them into most Java APIs as is (with the
> caveat that they are made for reading, not for writing).
>
> If you did really want to convert them to hash-maps or whatever, it's
> pretty easy to do so with a clojure.walk/postwalk-replace.
>
> On Friday, January 31, 2020 at 3:07:24 PM UTC-6, Jason Ross wrote:
>>
>> Hey I know this is super old post but what would the reverse look like,
>> eg. recursively convert Clojure to java map
>>
>> On Saturday, October 15, 2011 at 4:10:32 AM UTC-5, Baishampayan Ghose
>> wrote:
>>>
>>> > I have a Java Map contains Map of Maps/List (JSON like map) and have
>>> > to convert to Clojure map (This happens at Java - Clojure Interop), So
>>> > I have written a converter function 'as-clj-map' by modifying the
>>> > clojure walk functions, It works fine, but consume lot of cpu when the
>>> > data structure is quit big. Any suggestions to improve this code?
>>>
>>> What about using protocols for this job?
>>>
>>> (defprotocol ConvertibleToClojure
>>> (->clj [o]))
>>>
>>> (extend-protocol ConvertibleToClojure
>>> java.util.Map
>>> (->clj [o] (let [entries (.entrySet o)]
>>>(reduce (fn [m [^String k v]]
>>> (assoc m (keyword k) (->clj v)))
>>>{} entries)))
>>>
>>> java.util.List
>>> (->clj [o] (vec (map ->clj o)))
>>>
>>> java.lang.Object
>>> (->clj [o] o)
>>>
>>> nil
>>> (->clj [_] nil))
>>>
>>> (defn as-clj-map
>>> [m]
>>> (->clj m))
>>>
>>>
>>> Let me know if this works for you & meets your performance requirements.
>>>
>>> Regards,
>>> BG
>>>
>>> --
>>> Baishampayan Ghose
>>> b.ghose at gmail.com
>>>
>>>
--
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.
To view this discussion on the web visit
https://groups.google.com/d/msgid/clojure/a4762b64-5131-4b8f-b794-da3ce41a0c86%40googlegroups.com.
Re: Recursively convert Java Map to Clojure Map
You don't need that - Clojure maps *are* Java maps (they implement
java.util.Map) and you can pass them into most Java APIs as is (with the
caveat that they are made for reading, not for writing).
If you did really want to convert them to hash-maps or whatever, it's
pretty easy to do so with a clojure.walk/postwalk-replace.
On Friday, January 31, 2020 at 3:07:24 PM UTC-6, Jason Ross wrote:
>
> Hey I know this is super old post but what would the reverse look like,
> eg. recursively convert Clojure to java map
>
> On Saturday, October 15, 2011 at 4:10:32 AM UTC-5, Baishampayan Ghose
> wrote:
>>
>> > I have a Java Map contains Map of Maps/List (JSON like map) and have
>> > to convert to Clojure map (This happens at Java - Clojure Interop), So
>> > I have written a converter function 'as-clj-map' by modifying the
>> > clojure walk functions, It works fine, but consume lot of cpu when the
>> > data structure is quit big. Any suggestions to improve this code?
>>
>> What about using protocols for this job?
>>
>> (defprotocol ConvertibleToClojure
>> (->clj [o]))
>>
>> (extend-protocol ConvertibleToClojure
>> java.util.Map
>> (->clj [o] (let [entries (.entrySet o)]
>>(reduce (fn [m [^String k v]]
>> (assoc m (keyword k) (->clj v)))
>>{} entries)))
>>
>> java.util.List
>> (->clj [o] (vec (map ->clj o)))
>>
>> java.lang.Object
>> (->clj [o] o)
>>
>> nil
>> (->clj [_] nil))
>>
>> (defn as-clj-map
>> [m]
>> (->clj m))
>>
>>
>> Let me know if this works for you & meets your performance requirements.
>>
>> Regards,
>> BG
>>
>> --
>> Baishampayan Ghose
>> b.ghose at gmail.com
>>
>>
--
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.
To view this discussion on the web visit
https://groups.google.com/d/msgid/clojure/cfe49f86-1995-4098-ae89-208a46d2fc76%40googlegroups.com.
Re: Recursively convert Java Map to Clojure Map
Hey I know this is super old post but what would the reverse look like, eg.
recursively convert Clojure to java map
On Saturday, October 15, 2011 at 4:10:32 AM UTC-5, Baishampayan Ghose wrote:
>
> > I have a Java Map contains Map of Maps/List (JSON like map) and have
> > to convert to Clojure map (This happens at Java - Clojure Interop), So
> > I have written a converter function 'as-clj-map' by modifying the
> > clojure walk functions, It works fine, but consume lot of cpu when the
> > data structure is quit big. Any suggestions to improve this code?
>
> What about using protocols for this job?
>
> (defprotocol ConvertibleToClojure
> (->clj [o]))
>
> (extend-protocol ConvertibleToClojure
> java.util.Map
> (->clj [o] (let [entries (.entrySet o)]
>(reduce (fn [m [^String k v]]
> (assoc m (keyword k) (->clj v)))
>{} entries)))
>
> java.util.List
> (->clj [o] (vec (map ->clj o)))
>
> java.lang.Object
> (->clj [o] o)
>
> nil
> (->clj [_] nil))
>
> (defn as-clj-map
> [m]
> (->clj m))
>
>
> Let me know if this works for you & meets your performance requirements.
>
> Regards,
> BG
>
> --
> Baishampayan Ghose
> b.ghose at gmail.com
>
>
--
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.
To view this discussion on the web visit
https://groups.google.com/d/msgid/clojure/30c8edaf-bafe-4e78-9503-430d9f2c85ef%40googlegroups.com.
Re: Recursively convert Java Map to Clojure Map
On Sun, Oct 16, 2011 at 1:51 AM, Baishampayan Ghose b.gh...@gmail.com wrote: On Sun, Oct 16, 2011 at 11:16 AM, Jestan Nirojan jestanniro...@gmail.com wrote: Your solution worked, about 4x~5x improvement. Thanks a lot BG. Glad that it worked for you, Jestan. Protocols are usually the right approach for these kind of tasks. Why convert at all? Java maps can be used quite conveniently in Clojure. If it's because you need the map to be persistent, you might consider converting each map only when the user attempts to conj or assoc, rather than doing all the work up front. Since those aren't (yet!) protocols, I supposed you'd have to either use a non-standard conj and assoc, or create a wrapper around the Java Maps. Of course there are complications with all three of these solutions, so you'll have to choose carefully based on your needs. --Chouser -- 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
Re: Recursively convert Java Map to Clojure Map
I have a Java Map contains Map of Maps/List (JSON like map) and have
to convert to Clojure map (This happens at Java - Clojure Interop), So
I have written a converter function 'as-clj-map' by modifying the
clojure walk functions, It works fine, but consume lot of cpu when the
data structure is quit big. Any suggestions to improve this code?
What about using protocols for this job?
(defprotocol ConvertibleToClojure
(-clj [o]))
(extend-protocol ConvertibleToClojure
java.util.Map
(-clj [o] (let [entries (.entrySet o)]
(reduce (fn [m [^String k v]]
(assoc m (keyword k) (-clj v)))
{} entries)))
java.util.List
(-clj [o] (vec (map -clj o)))
java.lang.Object
(-clj [o] o)
nil
(-clj [_] nil))
(defn as-clj-map
[m]
(-clj m))
Let me know if this works for you meets your performance requirements.
Regards,
BG
--
Baishampayan Ghose
b.ghose at gmail.com
--
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
Re: Recursively convert Java Map to Clojure Map
Your solution worked, about 4x~5x improvement.
Thanks a lot BG.
regards.
-Jestan Nirojan
On Oct 15, 2:10 pm, Baishampayan Ghose b.gh...@gmail.com wrote:
I have a Java Map contains Map of Maps/List (JSON like map) and have
to convert to Clojure map (This happens at Java - Clojure Interop), So
I have written a converter function 'as-clj-map' by modifying the
clojure walk functions, It works fine, but consume lot of cpu when the
data structure is quit big. Any suggestions to improve this code?
What about using protocols for this job?
(defprotocol ConvertibleToClojure
(-clj [o]))
(extend-protocol ConvertibleToClojure
java.util.Map
(-clj [o] (let [entries (.entrySet o)]
(reduce (fn [m [^String k v]]
(assoc m (keyword k) (-clj v)))
{} entries)))
java.util.List
(-clj [o] (vec (map -clj o)))
java.lang.Object
(-clj [o] o)
nil
(-clj [_] nil))
(defn as-clj-map
[m]
(-clj m))
Let me know if this works for you meets your performance requirements.
Regards,
BG
--
Baishampayan Ghose
b.ghose at gmail.com
--
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
Re: Recursively convert Java Map to Clojure Map
On Sun, Oct 16, 2011 at 11:16 AM, Jestan Nirojan jestanniro...@gmail.com wrote: Your solution worked, about 4x~5x improvement. Thanks a lot BG. Glad that it worked for you, Jestan. Protocols are usually the right approach for these kind of tasks. Regards, BG -- Baishampayan Ghose b.ghose at gmail.com -- 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
