proofManagerLib.set

STRUCTURE

SYNOPSIS

Limits the number of proof states saved on the subgoal package backup list.

DESCRIPTION

The assignable variable set_backup is initially set to 12. Its value is one less than the maximum number of proof states that may be saved on the backup list. Adding a new proof state (by, for example, a call to expand) after the maximum is reached causes the earliest proof state on the list to be discarded. For a description of the subgoal package, see set_goal.

EXAMPLE

- set_backup 0;
()  unit

- g `(HD[1;2;3] = 1) /\ (TL[1;2;3] = [2;3])`;
> val it =
    Proof manager status: 1 proof.
    1. Incomplete:
         Initial goal:
         (HD [1; 2; 3] = 1) /\ (TL [1; 2; 3] = [2; 3])
         
     : proofs

- e CONJ_TAC;
OK..
2 subgoals:
> val it =
    TL [1; 2; 3] = [2; 3]
    
    
    HD [1; 2; 3] = 1
    
     :proof

- e (REWRITE_TAC[listTheory.HD]);
OK..

Goal proved.
|- HD [1; 2; 3] = 1

Remaining subgoals:
> val it =
    TL [1; 2; 3] = [2; 3]
    
     : proof

- b();
> val it =
    TL [1; 2; 3] = [2; 3]
    
    
    HD [1; 2; 3] = 1
    
     : proof

- b();
! Uncaught exception: 
! CANT_BACKUP_ANYMORE

SEEALSO

set_goal, restart, backup, restore, save, set_backup, expand, expandf, p, top_thm, top_goal