(**************************************************************************)
include "Legacy-1/definitions.ma".
-(*
+
default "equality"
- cic:/Coq/Init/Logic/eq.ind
- cic:/Coq/Init/Logic/sym_eq.con
- cic:/Coq/Init/Logic/trans_eq.con
- cic:/Coq/Init/Logic/eq_ind.con
- cic:/Coq/Init/Logic/eq_ind_r.con
- cic:/Coq/Init/Logic/eq_rec.con
- cic:/Coq/Init/Logic/eq_rec_r.con
- cic:/Coq/Init/Logic/eq_rect.con
- cic:/Coq/Init/Logic/eq_rect_r.con
- cic:/Coq/Init/Logic/f_equal.con
- cic:/matita/legacy/coq/f_equal1.con.
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/eq.ind
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/sym_eq.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/trans_eq.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/eq_ind.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/eq_ind_r.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/eq_rec.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/eq_rec_r.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/eq_rect.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/eq_rect_r.con
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/f_equal.con
+ cic:/matita/LAMBDA-TYPES/Legacy-2/preamble/f_equal_sym.con.
default "true"
- cic:/Coq/Init/Logic/True.ind.
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/True.ind.
default "false"
- cic:/Coq/Init/Logic/False.ind.
+ cic:/matita/LAMBDA-TYPES/Legacy-1/preamble/False.ind.
default "absurd"
- cic:/Coq/Init/Logic/absurd.con.
+ cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/absurd.con.
-(* aritmetic operators *)
+interpretation "Coq's natural plus" 'plus x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/plus.con x y).
+interpretation "Coq's natural minus" 'minus x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/minus.con x y).
+interpretation "Coq's logical and" 'and x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/land.ind#xpointer(1/1) x y).
+interpretation "Coq's logical or" 'or x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/or.ind#xpointer(1/1) x y).
+interpretation "Coq's logical not" 'not x = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/not.con x).
+interpretation "Coq's exists" 'exists \eta.x = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/ex.ind#xpointer(1/1) _ x).
+interpretation "Coq's natural 'less or equal to'" 'leq x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/le.ind#xpointer(1/1) x y).
+interpretation "Coq's natural 'less than'" 'lt x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/lt.con x y).
+interpretation "Coq's leibnitz's equality" 'eq x y = (cic:/matita/LAMBDA-TYPES/Legacy-1/coq/defs/eq.ind#xpointer(1/1) _ x y).
-interpretation "Coq's natural plus" 'plus x y = (cic:/Coq/Init/Peano/plus.con x y).
-*)
+theorem f_equal_sym: \forall A,B:Set.\forall f:A\to B.\forall x,y.
+ x = y \to (f y) = (f x).
+ intros; symmetry.
+ apply cic:/matita/LAMBDA-TYPES/Legacy-1/coq/props/f_equal.con.
+ assumption.
+qed.