P
A:Prop. Dec(A) 
Prop l) == 
i:
. i < ||l|| & x = l[i] TT:Type, x:T, l:T List. (x l) Prop| Some definitions of interest. | |
| decidable | Def Dec(P) == P P |
| Thm* A:Prop. Dec(A) Prop | |
| l_member | Def (x l) == i:. i < ||l|| & x = l[i] T |
| Thm* T:Type, x:T, l:T List. (x l) Prop |
About:
 |  |  |  |  |  |  |
 |  |  |  |