## counts number in a list

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Ehsan
Posts: 8
Joined: Thu Jul 12, 2012 7:39 am

### counts number in a list

Hi every one

I need a function count numbers in a list for example
(count-numbers '(3 4 5 a b c d 6 ) ) -> 4

Goheeca
Posts: 271
Joined: Thu May 10, 2012 12:54 pm
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### Re: counts number in a list

You can use the loop macro (search for a count clause) with a numberp predicate.
cl-2dsyntax is my attempt to create a Python-like reader. My mirror of CLHS (and the dark themed version). Temporary mirrors of aferomentioned: CLHS and a dark version.

nuntius
Posts: 538
Joined: Sat Aug 09, 2008 10:44 am
Location: Newton, MA

### Re: counts number in a list

let, dolist, incf, and numberp would also work.

A recursive helper function could be used to eliminate the let, dolist, and incf; some classes prefer recursive solutions.

Ehsan
Posts: 8
Joined: Thu Jul 12, 2012 7:39 am

### Re: counts number in a list

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