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15 include "basic_2/syntax/cext2.ma".
17 (* CONTEXT-AWARE SYNTACTIC EQUIVALENCE FOR BINDERS **************************)
19 definition ceq_ext: lenv → relation bind ≝
22 (* Basic properties *********************************************************)
24 lemma ceq_ext_refl (L): reflexive … (ceq_ext L).
25 /2 width=1 by ext2_refl/ qed.
27 (* Basic inversion lemmas ***************************************************)
29 lemma ceq_ext_inv_eq: ∀L,I1,I2. ceq_ext L I1 I2 → I1 = I2.
30 #L #I1 #I2 * -I1 -I2 //