Hi,
I struggling to find a way to alter a value in a map that resides in a
vector.
Given I have the following
(def result (ref [ { :id 1 :emails { "yi...@mail.com" 1}} ] ) )
I like to alter the result in a transaction to become
[{:id 1 :emails { "yi...@mail.com" 2}}]; increment the counter
Hi,
Am Montag, 3. Juni 2013 22:16:54 UTC+2 schrieb Yinka Erinle:
>
> Given I have the following
> (def result (ref [ { :id 1 :emails { "yi...@mail.com " 1}} ]
> ) )
>
> I like to alter the result in a transaction to become
> [{:id 1 :emails { "yi...@mail.com " 2}}]; increment the
> counter
Thanks Meikel for the prompt reply, that does it.
Please can you elaborate on how I can use the solution below to update a
particular entry in the vector.
[{:id 1 :email {"a...@mail.com 1}}
{:id 2 :email {"d...@mail.com 1}}
{:id 3 :email {"g...@mail.com 2}}]
So I will like to write a functi
You *can* update this inside the vector, but if you want to key by :id, I
would personally recommend, you put the email data into a map and look it
up by :id, like this:
{1 {:id 1 :email {"a...@mail.com 1}}
2 {:id 2 :email {"d...@mail.com 1}}
3 {:id 3 :email {"g...@mail.com 2}}}
Best,
Alex
O
Solutions seem to depend on whether you have two or more mail addresses in
a ':emails' section or not.
If you have, you should identify the mail address of which you want to
increment the value.
Anyway, try below:
(dosync
(alter result
(fn [v]
(mapv second
(update-in (into {}
I've seen some interesting responses, but here's my solution. user> (def example
(ref
[{:id 1 :email {"a...@mail.com" 1}}
{:id 2 :email {"d...@mail.com" 1}}
{:id 3 :email {"g...@mail.com" 2}}
{:id 4 :email {"f...@mail.com" 2}}]))
#'user/example
user>
Hi,
Am Mittwoch, 12. Juni 2013 06:39:59 UTC+2 schrieb Kelker Ryan:
>
> user> (defn update-counter [id xs]
>
> (let [at-after (drop-while #(not= id (:id %)) @xs)
> to-modify (-> at-after first :email)
> mod-key (-> to-modify keys first)
> location (
Here's the refactored version.user> (def example
(ref
[{:id 1 :email {"a...@mail.com" 1}}
{:id 2 :email {"d...@mail.com" 1}}
{:id 3 :email {"g...@mail.com" 2}}
{:id 4 :email {"f...@mail.com" 2}}]))
#'user/example
user>
(defn
Hello,
A note about the code organization : I think you should strive to
separate the code that does side effects from the code that works on
the datastructures.
This means you could refactor your refactored version as such:
=> (def example
(ref
[{:id 1 :email {"a...@mail.com" 1}}
