comparison src/Predicates.v @ 448:2740b8a23cce

Proofreading pass through Chapter 3
author Adam Chlipala <adam@chlipala.net>
date Fri, 17 Aug 2012 14:19:59 -0400
parents 89c67796754e
children 79190c225f1a
comparison
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447:9e3333bd08a1 448:2740b8a23cce
847 847
848 848
849 (* begin hide *) 849 (* begin hide *)
850 (* In-class exercises *) 850 (* In-class exercises *)
851 851
852 (* EX: Define a type [prop] of simple boolean formulas made up only of truth, falsehood, binary conjunction, and binary disjunction. Define an inductive predicate [holds] that captures when [prop]s are valid, and define a predicate [falseFree] that captures when a [prop] does not contain the "false" formula. Prove that every false-free [prop] is valid. *) 852 (* EX: Define a type [prop] of simple Boolean formulas made up only of truth, falsehood, binary conjunction, and binary disjunction. Define an inductive predicate [holds] that captures when [prop]s are valid, and define a predicate [falseFree] that captures when a [prop] does not contain the "false" formula. Prove that every false-free [prop] is valid. *)
853 853
854 (* begin thide *) 854 (* begin thide *)
855 Inductive prop : Set := 855 Inductive prop : Set :=
856 | Tru : prop 856 | Tru : prop
857 | Fals : prop 857 | Fals : prop