Self-call inside condition

[pylover]

diagram: Authentication
version: 1.0
author: pylover

sequence: Login

bob -> db: ensure()
  if: not db.is_connected
    db -> db: connect()

 DIAGRAM: Authentication                                                  
 author: pylover                                                          
 version: 1.0                                                             
                                                                          
 SEQUENCE: Login                                                          
                                                                          
 +-----+                            +-----+                               
 | bob |                            | db  |                               
 +-----+                            +-----+                               
    |                                  |                                  
    |~~~ensure()~~~~~~~~~~~~~~~~~~~~~~>|                                  
    |                                  |                                  
    |                               *******                               
    |                               * if not db.is_connected              
    |                               *******                               
    |                                  |                                  
    |                                  |~~~connect()~~~+                  
    |                                  |               |                  
    |                                  |<--------------+                  
    |                                  |                                  
    |                               *******                               
    |                               * end if                              
    |                               *******                               
    |                                  |                                  
    |<---------------------------------|                                  
    |                                  |                                  
 +-----+                            +-----+                               
 | bob |                            | db  |                               
 +-----+                            +-----+