Re: New to Clojure, need some help

[Baishampayan Ghose]

Hi,

Does this work for you?

(remove #{:a} [:a :b :a :c :d :e])

Also, if you have a list of items you can have all of them in the same
set/predicate like so -

(remove #{:a :z :x} [:a :b :a :c :d :e :z :b :d :e :x :z])

Hope this helps.

Regards,
BG

On Thu, Aug 9, 2012 at 10:11 AM, Jason Long <jsn...@gmail.com> wrote:
> I am trying to remove every occurrence of a given element from a vector. I
> can use (filter #(== % a) v) where 'a' is the value to be removed and 'v' is
> the vector, but this returns 'a' and 'a' is the value i want to remove. So,
> how can i do this? I tried replacing 'filter' with 'remove' but it didn't
> like that. Also, can anyone tell me why != is not included for equality
> testing, that would make this problem easy.
>
> Thanks, Jason.
>
> P.S. I also need to be able replicate the problem, but instead of removing a
> single item from the vector, I need to remove a list of items from the
> vector. I know I'm going to have to do some looping or recursing, but any
> help would be appreciated. Thanks
>
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--
Baishampayan Ghose
b.ghose at gmail.com

[Timothy Baldridge]

To clarify  Baishampayan's code, hash-sets in Clojure are functions:

=> (#{1} 1)

1

=> (#{1} 2)

nil

Nil and false in Clojure are the same thing, 

So Baishampayan's example: 

(remove #{:a :z :x} [:a :b :a :c :d :e :z :b :d :e :x :z])

#{:a :z : x} will return nil if the value is not in the vector, nil is considered false, and so the not found value is removed from the seq.

Timothy

[Baishampayan Ghose]

On Thu, Aug 9, 2012 at 10:11 AM, Jason Long <jsn...@gmail.com> wrote:
> Also, can anyone tell me why != is not included for equality testing, that
> would make this problem easy.

To answer your other question, != in Clojure is called not=

Regards,
BG