1 | 1. t: Term 2. u: Term Type{i'} 3. w: t:{v:Term| u(v) }  as:(Label Term) List.
( x:Label. unprime(apply_alist(as;x;x)) = x)  unprime(term_subst(as;t)) = unprime(t) 4. x: Label 5. as: (Label Term) List 6. x:Label. unprime(apply_alist(as;x;x)) = x unprime(apply_alist(as;x;x')) = unprime(x') |