4.39 PreviousPO

Syntax

  pv

Use

This command enables to go to the first previous unproved proof obligations, if there is one. If there is no more unproved proof obligation left, command pv is ineffective.

Example

The component have 2 operations, 1 proved proof obligation and 3 unproved proof obligations. By launching the gs command, we get the following situation:


 
PRI> gs  
State of all PO  
    Initialisation  
        PO1 Proved      not(e5 = e1)  
        PO2 Unproved     e1 = e5  
    Calculus  
        PO1 Unproved    not(e2 = e5)  
        PO2 Unproved    e5 = e1  
End  
 


Let suppose that the current proof operation is Calculus.1. The user goes to the first previous unproved obligation.


 
PRI> pv  
Current PO : Initialisation.2  
 


By repeating the command, we go to proof obligation Calculus.2.


 
PRI> pv  
Current PO : Calculus.2