src/HOL/IOA/Solve.thy

Calculation.thy: Setup transitivity rules for calculational proofs.

(*  Title:      HOL/IOA/Solve.thy
    ID:         $Id$
    Author:     Tobias Nipkow & Konrad Slind
    Copyright   1994  TU Muenchen

Weak possibilities mapping (abstraction)
*)

Solve = IOA +

constdefs

  is_weak_pmap :: "['c => 'a, ('action,'c)ioa,('action,'a)ioa] => bool"
  "is_weak_pmap f C A ==                          
   (!s:starts_of(C). f(s):starts_of(A)) &        
   (!s t a. reachable C s &                      
            (s,a,t):trans_of(C)                  
            --> (if a:externals(asig_of(C)) then 
                   (f(s),a,f(t)):trans_of(A)     
                 else f(s)=f(t)))"

end