let S be non empty non void ManySortedSign ; for s1, s2 being SortSymbol of S
for A being feasible MSAlgebra of S
for f being Function st f is_e.translation_of A,s1,s2 holds
( f is Function of (the Sorts of A . s1),(the Sorts of A . s2) & the Sorts of A . s1 <> {} & the Sorts of A . s2 <> {} )
let s1, s2 be SortSymbol of S; for A being feasible MSAlgebra of S
for f being Function st f is_e.translation_of A,s1,s2 holds
( f is Function of (the Sorts of A . s1),(the Sorts of A . s2) & the Sorts of A . s1 <> {} & the Sorts of A . s2 <> {} )
let A be feasible MSAlgebra of S; for f being Function st f is_e.translation_of A,s1,s2 holds
( f is Function of (the Sorts of A . s1),(the Sorts of A . s2) & the Sorts of A . s1 <> {} & the Sorts of A . s2 <> {} )
let f be Function; ( f is_e.translation_of A,s1,s2 implies ( f is Function of (the Sorts of A . s1),(the Sorts of A . s2) & the Sorts of A . s1 <> {} & the Sorts of A . s2 <> {} ) )
assume
f is_e.translation_of A,s1,s2
; ( f is Function of (the Sorts of A . s1),(the Sorts of A . s2) & the Sorts of A . s1 <> {} & the Sorts of A . s2 <> {} )
then consider o being OperSymbol of S such that
A1:
the_result_sort_of o = s2
and
A2:
ex i being Element of NAT st
( i in dom (the_arity_of o) & (the_arity_of o) /. i = s1 & ex a being Function st
( a in Args o,A & f = transl o,i,a,A ) )
by Def5;
Result o,A = the Sorts of A . (the_result_sort_of o)
by PRALG_2:10;
hence
( f is Function of (the Sorts of A . s1),(the Sorts of A . s2) & the Sorts of A . s1 <> {} & the Sorts of A . s2 <> {} )
by A1, A2, Def1, Th3, Th10; verum