retroforth/example/Primes.forth

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This is a quick and dirty way to find prime numbers in a set.
~~~
{{
#2 'NextPrime var<n>
:extract (s-s)
[ @NextPrime dup-pair eq?
[ drop-pair TRUE ]
[ mod n:-zero? ] choose ] array:filter ;
---reveal---
:get-primes (s-s)
#2 !NextPrime
dup fetch [ extract &NextPrime v:inc ] times ;
}}
~~~
And a test:
~~~
:create-set (-a)
here #3000 , #2 #3002 [ dup , n:inc ] times drop ;
create-set get-primes [ n:put sp ] array:for-each
~~~