This is more an itch than a problem: yesterday in CB came out a little simple quiz reported by 1nickt (who obviously knows many different solutions to the quiz). The problem sounded like: write a sub that receives arrays of strings and print them interleaved. I added the constraint that print order had to be not just mixed but the first element of each array, then the second etc..

obviously there are many, simple, ways to accomplish this with or without core modules. First thing that i supposed was to spot the max length of received arrays and build a loop (and this approach works ok).

But and here the itch, after a while i started mumbling about shift to death arrays skipping the max length computing and I ended with:

# DO NOT RUN THIS!!

perl -e "sub inter{map {print shift @$_} @_; &inter} inter([1],[1,2],[
+1,2,3],[1,2,3,4,5])"

# OUT
Out of memory!
11112223345
[download]

Which unfortunately, while printing the correct result, bring to an undesired Out of memory!

Now I understand that it goes out of memory because nothing stops the recursion, so i tried to break it but with no luck: inserting in the top of the sub exit unless $_[0][0] just prints first elements of each array and exits, &inter if $_[0][0] at the end does the same.

Some insight?

L*