You usually need to tell the function when it should stop recursing. In this case, you can do 
&inter if grep @$_, @_

[download]

You can also use the tail recursion goto &inter here, as there's nothing happening after returning from the recursion.

($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,

[download]

In reply to Re: understand and prevent 'Out of memory!' during sub recursion by choroba
in thread understand and prevent 'Out of memory!' during sub recursion by Discipulus

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