[MacPorts] #40169: Error: Unable to open port: invalid command name "port::run_callbacks"

[MacPorts]

#40169: Error: Unable to open port: invalid command name "port::run_callbacks"
----------------------+--------------------------------
 Reporter:  guivho@…  |      Owner:  macports-tickets@…
     Type:  defect    |     Status:  new
 Priority:  Normal    |  Milestone:
Component:  base      |    Version:  2.2.0
 Keywords:            |       Port:
----------------------+--------------------------------
 Once a week I successfully run following three commands:
 {{{
 port selfupdate
 port installed
 port outdated
 }}}
 However, since a couple of weeks I get following error output
 as soon as I run `sudo port upgrade outdated':

 {{{
 Error: Unable to open port: invalid command name "port::run_callbacks"
 To report a bug, follow the instructions in the guide:
     http://guide.macports.org/#project.tickets
 }}}

 I have searched the web, 'The problem Hotlist', 'the search page' etc but
 I'm still clueless.

 This used to work but unfortunately I do not know when exactly it stopped
 working.

 My list of outdated ports is growing, so I really need to upgrade :(

 Please advise,

 Guido

-- 
Ticket URL: <https://trac.macports.org/ticket/40169>
MacPorts <http://www.macports.org/>
Ports system for OS X