for A being preIfWhileAlgebra
for C, I being Element of A
for S being non empty set
for T being Subset of S
for s being Element of S
for f being ExecutionFunction of A,S,T
for r being non empty FinSequence of S st r . 1 = f . (s,C) & r . (len r) nin T & ( for i being Nat st 1 <= i & i < len r holds
( r . i in T & r . (i + 1) = f . ((r . i),(I \; C)) ) ) holds
f . (s,(while (C,I))) = r . (len r)