I think you can argue both ways.

My point was just that sometimes the base case for a recursion sometimes is much simpler than it seems. Your original code does roughly for both base case and recursive case (it iterates over the list and returns true if some condition holds), which is usually a sign that the base case could be chosen simpler.

I frequently fell into that trap, resulting in longer and error-prone code, so I'd thought it's best to point out.

Usually I'd handle such a case like that: 

sub sumTo {
   return 0 if $_[0] == 0 && @_ > 1;
   _sumTo(@_);     # or &_sumTo if you want to be cryptic
}

sub _sumTo {
   my ($target, @list) = @_;
   return 1 if $target == 0;
   return 0 if @list == 0;
   # here goes the recursive call to _sumTo
}

[download]

If you don't like wrapper functions you can use caller to determine if the current call is recursive.

In reply to Re^6: Recursion problem by moritz
in thread Recursion problem by someone202

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