4 header {* Lambda Cube Examples *}
13 H. Barendregt. Introduction to Generalised Type Systems.
14 J. Functional Programming.
17 method_setup depth_solve = {*
18 Method.thms_args (fn thms => Method.METHOD (fn facts =>
19 (DEPTH_SOLVE (HEADGOAL (ares_tac (facts @ thms))))))
22 method_setup depth_solve1 = {*
23 Method.thms_args (fn thms => Method.METHOD (fn facts =>
24 (DEPTH_SOLVE_1 (HEADGOAL (ares_tac (facts @ thms))))))
27 method_setup strip_asms = {*
28 let val strip_b = thm "strip_b" and strip_s = thm "strip_s" in
29 Method.thms_args (fn thms => Method.METHOD (fn facts =>
30 REPEAT (resolve_tac [strip_b, strip_s] 1 THEN DEPTH_SOLVE_1 (ares_tac (facts @ thms) 1))))
35 subsection {* Simple types *}
37 lemma "A:* |- A->A : ?T"
38 by (depth_solve rules)
40 lemma "A:* |- Lam a:A. a : ?T"
41 by (depth_solve rules)
43 lemma "A:* B:* b:B |- Lam x:A. b : ?T"
44 by (depth_solve rules)
46 lemma "A:* b:A |- (Lam a:A. a)^b: ?T"
47 by (depth_solve rules)
49 lemma "A:* B:* c:A b:B |- (Lam x:A. b)^ c: ?T"
50 by (depth_solve rules)
52 lemma "A:* B:* |- Lam a:A. Lam b:B. a : ?T"
53 by (depth_solve rules)
56 subsection {* Second-order types *}
58 lemma (in L2) "|- Lam A:*. Lam a:A. a : ?T"
59 by (depth_solve rules)
61 lemma (in L2) "A:* |- (Lam B:*.Lam b:B. b)^A : ?T"
62 by (depth_solve rules)
64 lemma (in L2) "A:* b:A |- (Lam B:*.Lam b:B. b) ^ A ^ b: ?T"
65 by (depth_solve rules)
67 lemma (in L2) "|- Lam B:*.Lam a:(Pi A:*.A).a ^ ((Pi A:*.A)->B) ^ a: ?T"
68 by (depth_solve rules)
71 subsection {* Weakly higher-order propositional logic *}
73 lemma (in Lomega) "|- Lam A:*.A->A : ?T"
74 by (depth_solve rules)
76 lemma (in Lomega) "B:* |- (Lam A:*.A->A) ^ B : ?T"
77 by (depth_solve rules)
79 lemma (in Lomega) "B:* b:B |- (Lam y:B. b): ?T"
80 by (depth_solve rules)
82 lemma (in Lomega) "A:* F:*->* |- F^(F^A): ?T"
83 by (depth_solve rules)
85 lemma (in Lomega) "A:* |- Lam F:*->*.F^(F^A): ?T"
86 by (depth_solve rules)
91 lemma (in LP) "A:* |- A -> * : ?T"
92 by (depth_solve rules)
94 lemma (in LP) "A:* P:A->* a:A |- P^a: ?T"
95 by (depth_solve rules)
97 lemma (in LP) "A:* P:A->A->* a:A |- Pi a:A. P^a^a: ?T"
98 by (depth_solve rules)
100 lemma (in LP) "A:* P:A->* Q:A->* |- Pi a:A. P^a -> Q^a: ?T"
101 by (depth_solve rules)
103 lemma (in LP) "A:* P:A->* |- Pi a:A. P^a -> P^a: ?T"
104 by (depth_solve rules)
106 lemma (in LP) "A:* P:A->* |- Lam a:A. Lam x:P^a. x: ?T"
107 by (depth_solve rules)
109 lemma (in LP) "A:* P:A->* Q:* |- (Pi a:A. P^a->Q) -> (Pi a:A. P^a) -> Q : ?T"
110 by (depth_solve rules)
112 lemma (in LP) "A:* P:A->* Q:* a0:A |-
113 Lam x:Pi a:A. P^a->Q. Lam y:Pi a:A. P^a. x^a0^(y^a0): ?T"
114 by (depth_solve rules)
117 subsection {* Omega-order types *}
119 lemma (in L2) "A:* B:* |- Pi C:*.(A->B->C)->C : ?T"
120 by (depth_solve rules)
122 lemma (in Lomega2) "|- Lam A:*.Lam B:*.Pi C:*.(A->B->C)->C : ?T"
123 by (depth_solve rules)
125 lemma (in Lomega2) "|- Lam A:*.Lam B:*.Lam x:A. Lam y:B. x : ?T"
126 by (depth_solve rules)
128 lemma (in Lomega2) "A:* B:* |- ?p : (A->B) -> ((B->Pi P:*.P)->(A->Pi P:*.P))"
129 apply (strip_asms rules)
131 apply (depth_solve1 rules)
133 apply (depth_solve1 rules)
135 apply (depth_solve1 rules)
137 apply (depth_solve1 rules)
141 apply (depth_solve1 rules)
142 apply (erule pi_elim)
144 apply (erule pi_elim)
150 subsection {* Second-order Predicate Logic *}
152 lemma (in LP2) "A:* P:A->* |- Lam a:A. P^a->(Pi A:*.A) : ?T"
153 by (depth_solve rules)
155 lemma (in LP2) "A:* P:A->A->* |-
156 (Pi a:A. Pi b:A. P^a^b->P^b^a->Pi P:*.P) -> Pi a:A. P^a^a->Pi P:*.P : ?T"
157 by (depth_solve rules)
159 lemma (in LP2) "A:* P:A->A->* |-
160 ?p: (Pi a:A. Pi b:A. P^a^b->P^b^a->Pi P:*.P) -> Pi a:A. P^a^a->Pi P:*.P"
161 -- {* Antisymmetry implies irreflexivity: *}
162 apply (strip_asms rules)
164 apply (depth_solve1 rules)
166 apply (depth_solve1 rules)
170 apply (depth_solve1 rules)
172 apply (depth_solve1 rules)
174 apply (depth_solve1 rules)
175 apply (erule pi_elim, assumption, assumption?)+
179 subsection {* LPomega *}
181 lemma (in LPomega) "A:* |- Lam P:A->A->*.Lam a:A. P^a^a : ?T"
182 by (depth_solve rules)
184 lemma (in LPomega) "|- Lam A:*.Lam P:A->A->*.Lam a:A. P^a^a : ?T"
185 by (depth_solve rules)
188 subsection {* Constructions *}
190 lemma (in CC) "|- Lam A:*.Lam P:A->*.Lam a:A. P^a->Pi P:*.P: ?T"
191 by (depth_solve rules)
193 lemma (in CC) "|- Lam A:*.Lam P:A->*.Pi a:A. P^a: ?T"
194 by (depth_solve rules)
196 lemma (in CC) "A:* P:A->* a:A |- ?p : (Pi a:A. P^a)->P^a"
197 apply (strip_asms rules)
199 apply (depth_solve1 rules)
201 apply (depth_solve1 rules)
202 apply (erule pi_elim, assumption, assumption)
206 subsection {* Some random examples *}
208 lemma (in LP2) "A:* c:A f:A->A |-
209 Lam a:A. Pi P:A->*.P^c -> (Pi x:A. P^x->P^(f^x)) -> P^a : ?T"
210 by (depth_solve rules)
212 lemma (in CC) "Lam A:*.Lam c:A. Lam f:A->A.
213 Lam a:A. Pi P:A->*.P^c -> (Pi x:A. P^x->P^(f^x)) -> P^a : ?T"
214 by (depth_solve rules)
217 "A:* a:A b:A |- ?p: (Pi P:A->*.P^a->P^b) -> (Pi P:A->*.P^b->P^a)"
218 -- {* Symmetry of Leibnitz equality *}
219 apply (strip_asms rules)
221 apply (depth_solve1 rules)
223 apply (depth_solve1 rules)
224 apply (erule_tac a = "Lam x:A. Pi Q:A->*.Q^x->Q^a" in pi_elim)
225 apply (depth_solve1 rules)
227 apply (erule imp_elim)
229 apply (depth_solve1 rules)
231 apply (depth_solve1 rules)
233 apply (depth_solve1 rules)
235 apply (depth_solve1 rules)