diff options
Diffstat (limited to 'proofs/signatures/er.plf')
-rw-r--r-- | proofs/signatures/er.plf | 65 |
1 files changed, 35 insertions, 30 deletions
diff --git a/proofs/signatures/er.plf b/proofs/signatures/er.plf index 8b559671e..9fcc9d4e8 100644 --- a/proofs/signatures/er.plf +++ b/proofs/signatures/er.plf @@ -64,13 +64,17 @@ (holds cln))) (holds cln))))) -; Takes a `list` of literals and a clause, `suffix`, adds the suffix to each -; literal and returns a list of clauses as a `cnf`. -(program clause_add_suffix_all ((list clause) (suffix clause)) cnf - (match list - (cln cnfn) - ((clc l rest) (cnfc (clc l suffix) - (clause_add_suffix_all rest suffix))))) +; Represents multiple conjoined clauses. +; There is a list, `heads` of literals, each of which is suffixed by the +; same `tail`. +(declare common_tail_cnf_t type) +(declare common_tail_cnf + (! heads clause + (! tail clause common_tail_cnf_t))) + +; A member of this type is a proof of a common_tail_cnf. +(declare common_tail_cnf_holds + (! cnf common_tail_cnf_t type)) ; This translates a definition witness value for the def: ; @@ -89,10 +93,6 @@ (! def (definition new old others) (! negOld lit (! mkNegOld (^ (lit_flip old) negOld) - (! provenCnf cnf - (! mkProvenCnf (^ (clause_add_suffix_all - others - (clc (neg new) (clc old cln))) provenCnf) ; If you can prove bottom from its clausal representation (! pf_continuation ; new v l_1 v l_2 v ... v l_n @@ -100,26 +100,31 @@ ; new v ~old (! pf_c2 (holds (clc (pos new) (clc negOld cln))) ; for each i <= n: l_i v ~new v old - (! pf_cs (cnf_holds provenCnf) + (! pf_cs (common_tail_cnf_holds + (common_tail_cnf + others + (clc (neg new) (clc old cln)))) (holds cln)))) ; Then you've proven bottom - (holds cln))))))))))) + (holds cln))))))))) -; This axiom is useful for converting a proof of some CNF formula (a value of -; type (cnf_holds ...)) into proofs of the constituent clauses (many values of -; type (holds ...)). +; These axioms are useful for converting a proof of some CNF formula represented +; using the `common_tail_cnf` type (a value of type `common_tail_cnf_holds`), +; into proofs of its constituent clauses (many values of type `holds`). ; Given -; 1. a proof of some cnf, first ^ rest, and -; 2. a proof continuation that -; a. takes in proofs of -; i. first and -; ii. rest and -; b. proceeds to prove bottom, -; proves bottom. -(declare cnfc_unroll_towards_bottom - (! first clause - (! rest cnf - (! pf (cnf_holds (cnfc first rest)) - (! pf_continuation (! r1 (holds first) (! r2 (cnf_holds rest) (holds cln))) - (holds cln)))))) - +; 1. a proof of some `common_tail_cnf` +; Then +; 1. the first axiom gives you a proof of the first `clause` therein and +; 2. the second gives you a proof of the rest of the `common_tail_cnf`. +(declare common_tail_cnf_prove_head + (! first lit + (! rest clause + (! tail clause + (! pf (common_tail_cnf_holds (common_tail_cnf (clc first rest) tail)) + (holds (clc first tail))))))) +(declare common_tail_cnf_prove_tail + (! first lit + (! rest clause + (! tail clause + (! pf (common_tail_cnf_holds (common_tail_cnf (clc first rest) tail)) + (common_tail_cnf_holds (common_tail_cnf rest tail))))))) |