19 |
19 |
20 @{text [display] "pred \<equiv> \<lambda>zs. \<forall>preds. orules \<longrightarrow> pred zs"} |
20 @{text [display] "pred \<equiv> \<lambda>zs. \<forall>preds. orules \<longrightarrow> pred zs"} |
21 |
21 |
22 and then ``register'' the definition inside a local theory. |
22 and then ``register'' the definition inside a local theory. |
23 To do the latter, we use the following wrapper for the function |
23 To do the latter, we use the following wrapper for the function |
24 @{ML LocalTheory.define}. The wrapper takes a predicate name, a syntax |
24 @{ML [index] define in LocalTheory}. The wrapper takes a predicate name, a syntax |
25 annotation and a term representing the right-hand side of the definition. |
25 annotation and a term representing the right-hand side of the definition. |
26 *} |
26 *} |
27 |
27 |
28 ML %linenosgray{*fun make_defn ((predname, mx), trm) lthy = |
28 ML %linenosgray{*fun make_defn ((predname, mx), trm) lthy = |
29 let |
29 let |
33 (thm, lthy') |
33 (thm, lthy') |
34 end*} |
34 end*} |
35 |
35 |
36 text {* |
36 text {* |
37 It returns the definition (as a theorem) and the local theory in which the |
37 It returns the definition (as a theorem) and the local theory in which the |
38 definition has been made. In Line 4, @{ML internalK in Thm} is a flag |
38 definition has been made. In Line 4, @{ML [index] internalK in Thm} is a flag |
39 attached to the theorem (others possibile flags are @{ML definitionK in Thm} |
39 attached to the theorem (others possibile flags are @{ML [index] definitionK in Thm} |
40 and @{ML axiomK in Thm}). These flags just classify theorems and have no |
40 and @{ML [index] axiomK in Thm}). These flags just classify theorems and have no |
41 significant meaning, except for tools that, for example, find theorems in |
41 significant meaning, except for tools that, for example, find theorems in |
42 the theorem database.\footnote{FIXME: put in the section about theorems.} We |
42 the theorem database.\footnote{FIXME: put in the section about theorems.} We |
43 also use @{ML empty_binding in Attrib} in Line 3, since the definitions for |
43 also use @{ML [index] empty_binding in Attrib} in Line 3, since the definitions for |
44 our inductive predicates are not meant to be seen by the user and therefore |
44 our inductive predicates are not meant to be seen by the user and therefore |
45 do not need to have any theorem attributes. A testcase for this function is |
45 do not need to have any theorem attributes. A testcase for this function is |
46 *} |
46 *} |
47 |
47 |
48 local_setup %gray {* fn lthy => |
48 local_setup %gray {* fn lthy => |
168 The user will state the introduction rules using meta-implications and |
168 The user will state the introduction rules using meta-implications and |
169 meta-quanti\-fications. In Line 4, we transform these introduction rules |
169 meta-quanti\-fications. In Line 4, we transform these introduction rules |
170 into the object logic (since definitions cannot be stated with |
170 into the object logic (since definitions cannot be stated with |
171 meta-connectives). To do this transformation we have to obtain the theory |
171 meta-connectives). To do this transformation we have to obtain the theory |
172 behind the local theory (Line 3); with this theory we can use the function |
172 behind the local theory (Line 3); with this theory we can use the function |
173 @{ML ObjectLogic.atomize_term} to make the transformation (Line 4). The call |
173 @{ML [index] atomize_term in ObjectLogic} to make the transformation (Line 4). The call |
174 to @{ML defn_aux} in Line 5 produces all right-hand sides of the |
174 to @{ML defn_aux} in Line 5 produces all right-hand sides of the |
175 definitions. The actual definitions are then made in Line 7. The result of |
175 definitions. The actual definitions are then made in Line 7. The result of |
176 the function is a list of theorems and a local theory (the theorems are |
176 the function is a list of theorems and a local theory (the theorems are |
177 registered with the local theory). A testcase for this function is |
177 registered with the local theory). A testcase for this function is |
178 *} |
178 *} |
435 the new local theory @{text "lthy'"}. From the local theory we extract |
435 the new local theory @{text "lthy'"}. From the local theory we extract |
436 the ambient theory in Line 6. We need this theory in order to certify |
436 the ambient theory in Line 6. We need this theory in order to certify |
437 the new predicates. In Line 8, we construct the types of these new predicates |
437 the new predicates. In Line 8, we construct the types of these new predicates |
438 using the given argument types. Next we turn them into terms and subsequently |
438 using the given argument types. Next we turn them into terms and subsequently |
439 certify them (Line 9 and 10). We can now produce the substituted introduction rules |
439 certify them (Line 9 and 10). We can now produce the substituted introduction rules |
440 (Line 11) using the function @{ML subst_free}. Line 14 and 15 just iterate |
440 (Line 11) using the function @{ML [index] subst_free}. Line 14 and 15 just iterate |
441 the proofs for all predicates. |
441 the proofs for all predicates. |
442 From this we obtain a list of theorems. Finally we need to export the |
442 From this we obtain a list of theorems. Finally we need to export the |
443 fixed variables @{text "Ps"} to obtain the schematic variables @{text "?Ps"} |
443 fixed variables @{text "Ps"} to obtain the schematic variables @{text "?Ps"} |
444 (Line 16). |
444 (Line 16). |
445 |
445 |
577 first two) and assumptions from the definition of the predicate (assumption |
577 first two) and assumptions from the definition of the predicate (assumption |
578 three to six). We need to treat these parameters and assumptions |
578 three to six). We need to treat these parameters and assumptions |
579 differently. In the code below we will therefore separate them into @{text |
579 differently. In the code below we will therefore separate them into @{text |
580 "params1"} and @{text params2}, respectively @{text "prems1"} and @{text |
580 "params1"} and @{text params2}, respectively @{text "prems1"} and @{text |
581 "prems2"}. To do this separation, it is best to open a subproof with the |
581 "prems2"}. To do this separation, it is best to open a subproof with the |
582 tactic @{ML SUBPROOF}, since this tactic provides us with the parameters (as |
582 tactic @{ML [index] SUBPROOF}, since this tactic provides us with the parameters (as |
583 list of @{ML_type cterm}s) and the assumptions (as list of @{ML_type thm}s). |
583 list of @{ML_type cterm}s) and the assumptions (as list of @{ML_type thm}s). |
584 The problem we have to overcome with @{ML SUBPROOF} |
584 The problem we have to overcome with @{ML SUBPROOF} |
585 is, however, that this tactic always expects us to completely discharge the |
585 is, however, that this tactic always expects us to completely discharge the |
586 goal (see Section~\ref{sec:simpletacs}). This is inconvenient for our |
586 goal (see Section~\ref{sec:simpletacs}). This is inconvenient for our |
587 gradual explanation of the proof here. To circumvent this inconvenience we |
587 gradual explanation of the proof here. To circumvent this inconvenience we |
625 First we calculate the values for @{text "params1/2"} and @{text "prems1/2"} |
625 First we calculate the values for @{text "params1/2"} and @{text "prems1/2"} |
626 from @{text "params"} and @{text "prems"}, respectively. To better see what is |
626 from @{text "params"} and @{text "prems"}, respectively. To better see what is |
627 going in our example, we will print out these values using the printing |
627 going in our example, we will print out these values using the printing |
628 function in Figure~\ref{fig:chopprint}. Since the tactic @{ML SUBPROOF} will |
628 function in Figure~\ref{fig:chopprint}. Since the tactic @{ML SUBPROOF} will |
629 supply us the @{text "params"} and @{text "prems"} as lists, we can |
629 supply us the @{text "params"} and @{text "prems"} as lists, we can |
630 separate them using the function @{ML chop}. |
630 separate them using the function @{ML [index] chop}. |
631 *} |
631 *} |
632 |
632 |
633 ML{*fun chop_test_tac preds rules = |
633 ML{*fun chop_test_tac preds rules = |
634 SUBPROOF_test (fn {params, prems, context, ...} => |
634 SUBPROOF_test (fn {params, prems, context, ...} => |
635 let |
635 let |
689 |
689 |
690 @{term [display] "\<forall>a b t. a \<noteq> b \<longrightarrow> fresh a t \<longrightarrow> fresh a (Lam a t)"} |
690 @{term [display] "\<forall>a b t. a \<noteq> b \<longrightarrow> fresh a t \<longrightarrow> fresh a (Lam a t)"} |
691 |
691 |
692 To use this premise with @{ML rtac}, we need to instantiate its |
692 To use this premise with @{ML rtac}, we need to instantiate its |
693 quantifiers (with @{text params1}) and transform it into rule |
693 quantifiers (with @{text params1}) and transform it into rule |
694 format (using @{ML "ObjectLogic.rulify"}. So we can modify the |
694 format (using @{ML [index] rulify in ObjectLogic}. So we can modify the |
695 subproof as follows: |
695 subproof as follows: |
696 *} |
696 *} |
697 |
697 |
698 ML %linenosgray{*fun apply_prem_tac i preds rules = |
698 ML %linenosgray{*fun apply_prem_tac i preds rules = |
699 SUBPROOF_test (fn {params, prems, context, ...} => |
699 SUBPROOF_test (fn {params, prems, context, ...} => |
852 |
852 |
853 text {* |
853 text {* |
854 In Line 4 we use the @{text prems} from the @{ML SUBPROOF} and resolve |
854 In Line 4 we use the @{text prems} from the @{ML SUBPROOF} and resolve |
855 them with @{text prem}. In the simple cases, that is where the @{text prem} |
855 them with @{text prem}. In the simple cases, that is where the @{text prem} |
856 comes from a non-recursive premise of the rule, @{text prems} will be |
856 comes from a non-recursive premise of the rule, @{text prems} will be |
857 just the empty list and the function @{ML MRS} does nothing. Similarly, in the |
857 just the empty list and the function @{ML [index] MRS} does nothing. Similarly, in the |
858 cases where the recursive premises of the rule do not have preconditions. |
858 cases where the recursive premises of the rule do not have preconditions. |
859 In case there are preconditions, then Line 4 discharges them. After |
859 In case there are preconditions, then Line 4 discharges them. After |
860 that we can proceed as before, i.e., check whether the outermost |
860 that we can proceed as before, i.e., check whether the outermost |
861 connective is @{text "\<forall>"}. |
861 connective is @{text "\<forall>"}. |
862 |
862 |
930 in |
930 in |
931 map_index intros_aux rules |
931 map_index intros_aux rules |
932 end*} |
932 end*} |
933 |
933 |
934 text {* |
934 text {* |
935 The iteration is done with the function @{ML map_index} since we |
935 The iteration is done with the function @{ML [index] map_index} since we |
936 need the introduction rule together with its number (counted from |
936 need the introduction rule together with its number (counted from |
937 @{text 0}). This completes the code for the functions deriving the |
937 @{text 0}). This completes the code for the functions deriving the |
938 reasoning infrastructure. It remains to implement some administrative |
938 reasoning infrastructure. It remains to implement some administrative |
939 code that strings everything together. |
939 code that strings everything together. |
940 *} |
940 *} |
943 |
943 |
944 text {* |
944 text {* |
945 We have produced various theorems (definitions, induction principles and |
945 We have produced various theorems (definitions, induction principles and |
946 introduction rules), but apart from the definitions, we have not yet |
946 introduction rules), but apart from the definitions, we have not yet |
947 registered them with the theorem database. This is what the functions |
947 registered them with the theorem database. This is what the functions |
948 @{ML LocalTheory.note} does. |
948 @{ML [index] note in LocalTheory} does. |
949 |
949 |
950 |
950 |
951 For convenience, we use the following |
951 For convenience, we use the following |
952 three wrappers this function: |
952 three wrappers this function: |
953 *} |
953 *} |
1025 @{text "mut_name.inducts"}, respectively (see previous paragraph). |
1025 @{text "mut_name.inducts"}, respectively (see previous paragraph). |
1026 |
1026 |
1027 Line 20 add further every introduction rule under its own name |
1027 Line 20 add further every introduction rule under its own name |
1028 (given by the user).\footnote{FIXME: what happens if the user did not give |
1028 (given by the user).\footnote{FIXME: what happens if the user did not give |
1029 any name.} Line 21 registers the induction principles. For this we have |
1029 any name.} Line 21 registers the induction principles. For this we have |
1030 to use some specific attributes. The first @{ML "case_names" in RuleCases} |
1030 to use some specific attributes. The first @{ML [index] case_names in RuleCases} |
1031 corresponds to the case names that are used by Isar to reference the proof |
1031 corresponds to the case names that are used by Isar to reference the proof |
1032 obligations in the induction. The second @{ML "consumes 1" in RuleCases} |
1032 obligations in the induction. The second @{ML "consumes 1" in RuleCases} |
1033 indicates that the first premise of the induction principle (namely |
1033 indicates that the first premise of the induction principle (namely |
1034 the predicate over which the induction proceeds) is eliminated. |
1034 the predicate over which the induction proceeds) is eliminated. |
1035 |
1035 |