General Presentation (tcl/tk)

The ProB Main Window

The menu bar contains the various commands to access the features of ProB. It includes the traditional "File" menu with a sub-menu "Recent Files" to quickly access the files previously opened in ProB. Notice the commands "Open\Save", "Reopen\Save" and "Reopen"; the latter reopens the currently opened file and reinitializes the state of the animation and the model checking processes completely. The "About" menu provides help on the tool and includes a command to check if an update is available on the ProB website. By default, ProB starts with a limited set of commands in the Beginner mode. The Normal mode gives access to more features and can be set in the menu "Preferences|User Mode".

Under the menu bar, the main window contains four panes:

  • In the top pane, the specification of the B machine is displayed with the syntax highlighted and can also be edited by typing directly in this pane; you can find out more about this editor and how to use external editors in our wiki page on editors.
  • At the bottom, the animation window is composed of three panes which display at the current point during the animation:
    1. The current state of the B machine (State Properties), listing the current values of the machine variables;
    2. The enabled operations (Enabled Operations), listing the operations whose preconditions and guards are true in this state (see here for what the different colours mean);
    3. The history of operations leading to this state (History).


The "Preferences" menu allows the various features of ProB to be configured. When ProB is started for the first time, it creates a file that stores those preferences.

  • The sub-menu "Font" changes the font size of the B specification displayed in the main window.

The next three commands correspond to groups of preferences displayed in separate pop-up windows.

  • The command "Animation Preferences" ... configures important aspects of ProB relative to the animation and model checking of the B specifications. These preferences influence directly the way ProB interprets the B specification and are described in "Animation and Visualisation", amongst others.
  • The command "Graphical Viewer Preferences" ... allows the user to set the options of the visualization tool used by ProB and the shapes and colors used to display the nodes of the state space.
  • The command "Syntax Highlight Preferences" ... allows the user to activate the syntax highlight of the B specification in the main window and also to select the various colors corresponding to the syntactic elements of the B notation.

IMPORTANT: Changes in the animation preferences take effect only after reloading the machine.