No-Free-Lunch Theorems state, roughly speaking, that the performance of all
search algorithms is the same when averaged over all possible objective
functions. This fact was precisely formulated for the first time in a now
famous paper by Wolpert and Macready, and then subsequently refined and
extended by several authors, always in the context of a set of functions with
discrete domain and codomain. Recently, Auger and Teytaud have shown that for
continuum domains there is typically no No-Free-Lunch theorems. In this paper
we provide another approach, which is simpler, requires less assumptions,
relates the discrete and continuum cases, and that we believe that clarifies
the role of the cardinality and structure of the domain
