Esempio : un po’ di “calcolo”
________fact = _f. _x. if x=0 then 1 else x * f (x-1)
fact = lfp(_fact )
_fact _1 = _fact (_fact _0) = _fact (_f) = _x. if x=0 then 1 else _
_fact _2 = _fact (_fact _1) = _x. if x=0 then 1 else
x * (if x-1=0 then 1 else _)
_fact _3 = _x. if x=0 then 1 else
x * (if x-1=0 then 1 else
____________________ (x-1) * (if x-2=0 then 1 else _))