[Newbies] block in recursion, Any cure for that kind of situation?

[Hilaire Fernandes]

I got an error "Attempt to evaluate a block that is already being 
evaluated", when I call in recursion a block like

carre := [:s1 :s2 :s3 :s4 :n |
	n >0 ifTrue:
		[carre valueWithArguments:  {(segment value: s1 value: s2).
			 (segment value: s2 value: s3).
			 (segment value: s3 value: s4).
			 (segment value: s1 value: s4).
			 n-1}]]

Hilaire