1 (**************************************************************************)
4 (* ||A|| A project by Andrea Asperti *)
6 (* ||I|| Developers: *)
7 (* ||T|| The HELM team. *)
8 (* ||A|| http://helm.cs.unibo.it *)
10 (* \ / This file is distributed under the terms of the *)
11 (* v GNU General Public License Version 2 *)
13 (**************************************************************************)
15 include "basic_2/notation/relations/lrsubeqf_4.ma".
16 include "basic_2/static/frees.ma".
18 (* RESTRICTED REFINEMENT FOR CONTEXT-SENSITIVE FREE VARIABLES ***************)
20 inductive lsubf: relation4 lenv rtmap lenv rtmap ≝
21 | lsubf_atom: ∀f. lsubf (⋆) f (⋆) f
22 | lsubf_push: ∀f1,f2,I,L1,L2,V. lsubf L1 f1 L2 f2 →
23 lsubf (L1.ⓑ{I}V) (↑f1) (L2.ⓑ{I}V) (↑f2)
24 | lsubf_next: ∀f1,f2,I,L1,L2,V. lsubf L1 f1 L2 f2 →
25 lsubf (L1.ⓑ{I}V) (⫯f1) (L2.ⓑ{I}V) (⫯f2)
26 | lsubf_peta: ∀f1,f,f2,L1,L2,W,V. L1 ⊢ 𝐅*⦃V⦄ ≡ f → f2 ⋓ f ≡ f1 →
27 lsubf L1 f1 L2 f2 → lsubf (L1.ⓓⓝW.V) (↑f1) (L2.ⓛW) (↑f2)
28 | lsubf_neta: ∀f1,f,f2,L1,L2,W,V. L1 ⊢ 𝐅*⦃V⦄ ≡ f → f2 ⋓ f ≡ f1 →
29 lsubf L1 f1 L2 f2 → lsubf (L1.ⓓⓝW.V) (⫯f1) (L2.ⓛW) (⫯f2)
33 "local environment refinement (context-sensitive free variables)"
34 'LRSubEqF L1 f1 L2 f2 = (lsubf L1 f1 L2 f2).
36 (* Basic inversion lemmas ***************************************************)
38 fact lsubf_inv_atom1_aux: ∀f1,f2,L1,L2. ⦃L1, f1⦄ ⫃𝐅* ⦃L2, f2⦄ → L1 = ⋆ →
40 #f1 #f2 #L1 #L2 * -f1 -f2 -L1 -L2
42 | #f1 #f2 #I #L1 #L2 #V #_ #H destruct
43 | #f1 #f2 #I #L1 #L2 #V #_ #H destruct
44 | #f1 #f #f2 #L1 #L2 #W #V #_ #_ #_ #H destruct
45 | #f1 #f #f2 #L1 #L2 #W #V #_ #_ #_ #H destruct
49 lemma lsubf_inv_atom1: ∀f1,f2,L2. ⦃⋆, f1⦄ ⫃𝐅* ⦃L2, f2⦄ →
51 /2 width=3 by lsubf_inv_atom1_aux/ qed-.
53 fact lsubf_inv_push1_aux: ∀f1,f2,L1,L2. ⦃L1, f1⦄ ⫃𝐅* ⦃L2, f2⦄ →
54 ∀g1,I,K1,X. f1 = ↑g1 → L1 = K1.ⓑ{I}X →
55 (∃∃g2,K2. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f2 = ↑g2 & L2 = K2.ⓑ{I}X) ∨
56 ∃∃g,g2,K2,W,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
57 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abbr & f2 = ↑g2 & L2 = K2.ⓛW & X = ⓝW.V.
58 #f1 #f2 #L1 #L2 * -f1 -f2 -L1 -L2
59 [ #f #g1 #J #K1 #X #_ #H destruct
60 | #f1 #f2 #I #L1 #L2 #V #HL12 #g1 #J #K1 #X #H1 #H2 destruct
61 /3 width=5 by injective_push, ex3_2_intro, or_introl/
62 | #f1 #f2 #I #L1 #L2 #V #_ #g1 #J #K1 #X #H elim (discr_next_push … H)
63 | #f1 #f2 #f #L1 #L2 #W #V #Hf2 #Hf1 #HL12 #g1 #J #K1 #X #H1 #H2 destruct
64 /3 width=11 by injective_push, ex7_5_intro, or_intror/
65 | #f1 #f2 #f #L1 #L2 #W #V #_ #_ #_ #g1 #J #K1 #X #H elim (discr_next_push … H)
69 lemma lsubf_inv_push1: ∀g1,f2,I,K1,L2,X. ⦃K1.ⓑ{I}X, ↑g1⦄ ⫃𝐅* ⦃L2, f2⦄ →
70 (∃∃g2,K2. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f2 = ↑g2 & L2 = K2.ⓑ{I}X) ∨
71 ∃∃g,g2,K2,W,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
72 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abbr & f2 = ↑g2 & L2 = K2.ⓛW & X = ⓝW.V.
73 /2 width=5 by lsubf_inv_push1_aux/ qed-.
75 fact lsubf_inv_next1_aux: ∀f1,f2,L1,L2. ⦃L1, f1⦄ ⫃𝐅* ⦃L2, f2⦄ →
76 ∀g1,I,K1,X. f1 = ⫯g1 → L1 = K1.ⓑ{I}X →
77 (∃∃g2,K2. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f2 = ⫯g2 & L2 = K2.ⓑ{I}X) ∨
78 ∃∃g,g2,K2,W,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
79 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abbr & f2 = ⫯g2 & L2 = K2.ⓛW & X = ⓝW.V.
80 #f1 #f2 #L1 #L2 * -f1 -f2 -L1 -L2
81 [ #f #g1 #J #K1 #X #_ #H destruct
82 | #f1 #f2 #I #L1 #L2 #V #_ #g1 #J #K1 #X #H elim (discr_push_next … H)
83 | #f1 #f2 #I #L1 #L2 #V #HL12 #g1 #J #K1 #X #H1 #H2 destruct
84 /3 width=5 by injective_next, ex3_2_intro, or_introl/
85 | #f1 #f2 #f #L1 #L2 #W #V #_ #_ #_ #g1 #J #K1 #X #H elim (discr_push_next … H)
86 | #f1 #f2 #f #L1 #L2 #W #V #Hf2 #Hf1 #HL12 #g1 #J #K1 #X #H1 #H2 destruct
87 /3 width=11 by injective_next, ex7_5_intro, or_intror/
91 lemma lsubf_inv_next1: ∀g1,f2,I,K1,L2,X. ⦃K1.ⓑ{I}X, ⫯g1⦄ ⫃𝐅* ⦃L2, f2⦄ →
92 (∃∃g2,K2. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f2 = ⫯g2 & L2 = K2.ⓑ{I}X) ∨
93 ∃∃g,g2,K2,W,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
94 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abbr & f2 = ⫯g2 & L2 = K2.ⓛW & X = ⓝW.V.
95 /2 width=5 by lsubf_inv_next1_aux/ qed-.
97 fact lsubf_inv_atom2_aux: ∀f1,f2,L1,L2. ⦃L1, f1⦄ ⫃𝐅* ⦃L2, f2⦄ → L2 = ⋆ →
99 #f1 #f2 #L1 #L2 * -f1 -f2 -L1 -L2
100 [ /2 width=1 by conj/
101 | #f1 #f2 #I #L1 #L2 #V #_ #H destruct
102 | #f1 #f2 #I #L1 #L2 #V #_ #H destruct
103 | #f1 #f #f2 #L1 #L2 #W #V #_ #_ #_ #H destruct
104 | #f1 #f #f2 #L1 #L2 #W #V #_ #_ #_ #H destruct
108 lemma lsubf_inv_atom2: ∀f1,f2,L1. ⦃L1, f1⦄ ⫃𝐅* ⦃⋆, f2⦄ →
110 /2 width=3 by lsubf_inv_atom2_aux/ qed-.
112 fact lsubf_inv_push2_aux: ∀f1,f2,L1,L2. ⦃L1, f1⦄ ⫃𝐅* ⦃L2, f2⦄ →
113 ∀g2,I,K2,W. f2 = ↑g2 → L2 = K2.ⓑ{I}W →
114 (∃∃g1,K1. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f1 = ↑g1 & L1 = K1.ⓑ{I}W) ∨
115 ∃∃g,g1,K1,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
116 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abst & f1 = ↑g1 & L1 = K1.ⓓⓝW.V.
117 #f1 #f2 #L1 #L2 * -f1 -f2 -L1 -L2
118 [ #f #g2 #J #K2 #X #_ #H destruct
119 | #f1 #f2 #I #L1 #L2 #V #HL12 #g2 #J #K2 #X #H1 #H2 destruct
120 /3 width=5 by injective_push, ex3_2_intro, or_introl/
121 | #f1 #f2 #I #L1 #L2 #V #_ #g2 #J #K2 #X #H elim (discr_next_push … H)
122 | #f1 #f2 #f #L1 #L2 #W #V #Hf2 #Hf1 #HL12 #g2 #J #K2 #X #H1 #H2 destruct
123 /3 width=9 by injective_push, ex6_4_intro, or_intror/
124 | #f1 #f2 #f #L1 #L2 #W #V #_ #_ #_ #g2 #J #K2 #X #H elim (discr_next_push … H)
128 lemma lsubf_inv_push2: ∀f1,g2,I,L1,K2,W. ⦃L1, f1⦄ ⫃𝐅* ⦃K2.ⓑ{I}W, ↑g2⦄ →
129 (∃∃g1,K1. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f1 = ↑g1 & L1 = K1.ⓑ{I}W) ∨
130 ∃∃g,g1,K1,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
131 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abst & f1 = ↑g1 & L1 = K1.ⓓⓝW.V.
132 /2 width=5 by lsubf_inv_push2_aux/ qed-.
134 fact lsubf_inv_next2_aux: ∀f1,f2,L1,L2. ⦃L1, f1⦄ ⫃𝐅* ⦃L2, f2⦄ →
135 ∀g2,I,K2,W. f2 = ⫯g2 → L2 = K2.ⓑ{I}W →
136 (∃∃g1,K1. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f1 = ⫯g1 & L1 = K1.ⓑ{I}W) ∨
137 ∃∃g,g1,K1,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
138 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abst & f1 = ⫯g1 & L1 = K1.ⓓⓝW.V.
139 #f1 #f2 #L1 #L2 * -f1 -f2 -L1 -L2
140 [ #f #g2 #J #K2 #X #_ #H destruct
141 | #f1 #f2 #I #L1 #L2 #V #_ #g2 #J #K2 #X #H elim (discr_push_next … H)
142 | #f1 #f2 #I #L1 #L2 #V #HL12 #g2 #J #K2 #X #H1 #H2 destruct
143 /3 width=5 by injective_next, ex3_2_intro, or_introl/
144 | #f1 #f2 #f #L1 #L2 #W #V #_ #_ #_ #g2 #J #K2 #X #H elim (discr_push_next … H)
145 | #f1 #f2 #f #L1 #L2 #W #V #Hf2 #Hf1 #HL12 #g2 #J #K2 #X #H1 #H2 destruct
146 /3 width=9 by injective_next, ex6_4_intro, or_intror/
150 lemma lsubf_inv_next2: ∀f1,g2,I,L1,K2,W. ⦃L1, f1⦄ ⫃𝐅* ⦃K2.ⓑ{I}W, ⫯g2⦄ →
151 (∃∃g1,K1. ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & f1 = ⫯g1 & L1 = K1.ⓑ{I}W) ∨
152 ∃∃g,g1,K1,V. K1 ⊢ 𝐅*⦃V⦄ ≡ g & g2 ⋓ g ≡ g1 &
153 ⦃K1, g1⦄ ⫃𝐅* ⦃K2, g2⦄ & I = Abst & f1 = ⫯g1 & L1 = K1.ⓓⓝW.V.
154 /2 width=5 by lsubf_inv_next2_aux/ qed-.
156 (* Basic properties *********************************************************)
158 lemma lsubf_refl: bi_reflexive … lsubf.
160 #L #I #V #IH #f elim (pn_split f) * /2 width=1 by lsubf_push, lsubf_next/