On 23 March 2012 14:47, Leandro Oliveira wrote:
> Thank you for all replies.
>
> Can I say that if you need remove an item you should use a map?
It depends entirely on how you intend to look up your values. If your
lookup is by the entire value, then sets make sense. If it's by only
part of a val
Sets are good when you have a collection of things, the precise order isn't
important to you, and you want to avoid duplicates. I used one in some code
recently where I wanted to maintain a collection of people who were co-authors
in a Clojure patch, and the input file I started with could ment
Thank you for all replies.
The reason that I was using set instead of map was to use the functions
from closure.set. I like them.
But now I agree that map is a better approach.
(select (fn [{:keys [id]}] (not= id 1)) xrel) is O(n). Right?
Can I say that if you need remove an item you should use
Disclaimer, I'm only looking at how I would want to write it. You may
need to do something else if you have specific performance
requirements.
clojure.set is probably your friend.
user=> (def xrel #{{:id 1, :foo "bar"} {:id 2, :foo "car"} {:id 3, :foo "dog"}})
#'user/xrel
user=> (use 'clojure.set
Might it be possible to use a map instead? Maps are designed to look values
up by a key which may differ from the value, which seems to be your use
case here.
If you have
{1 {:id 1, :foo "bar"},
2 {:id 2, :foo "car"}}
You can just do
(disj my-map 2)
To convert the original set into a map, you
On Thu, Mar 22, 2012 at 10:32 PM, Cedric Greevey wrote:
(into #{} (remove #(= (:id %) foo) input-set))
> You could stop when :id foo got hit by using a loop/recur, and save half the
> iterations on average.
Clarification: stop comparing to match the :id key against the target.
You'd have to con
On Wed, Mar 21, 2012 at 5:00 PM, Leandro Oliveira wrote:
> Hi all,
>
> I have a set of hash like this:
>
> #{{:id 1, :foo "bar"} {:id 2, :foo "car"}}
>
> and I'd like to remove an item based on its id value.
>
> Unfortunately, disj requires that I pass the whole map as key to remove it.
>
> Can I
