Release 10.1A: OpenEdge Development:
Debugging and Troubleshooting

Watches pane

The watches pane keeps track of variables, buffer fields, attributes, data, and built-in 4GL functions on which a watch is set. For more information on functions as watches, see the "Watches for built-in functions" section.

The watches pane has a context (right-click) menu containing the following options: Copy, Cut, Paste, Add Watch (adds a new variable to the watches pane), Remove Watch, and Dataview (displays attribute or field information for the selected variable in the Dataview dialog box).

You can add a watch by:

Entering the watch into the last line of the watches pane directly.
Entering the watch in the Add Watch dialog box. For more information, see the "Add Watch dialog box" section.
Selecting text in the source code pane, or selecting a variable or parameter in the variables pane, and then choosing the Add Watch option on the context (right-click) menu.
Selecting text in the source code pane and dragging it to the watches pane. For more information, see the "Drag-and-drop watches" section.
Selecting an entity in the Dataview dialog box and choosing the Add Watch button.

Note the following with respect to validity checking of the selected text:

Selected text that is improperly formatted displays “** Error **” in its value cell.
Selected text that is properly formatted but that refers to an out-of-scope or nonexistent variable displays “** Unavailable **” in its value cell.

Valid watch formats are any of the following:

[ VARIABLE | FIELD | PARAMETER ] name

handle:attribute

widget-name:attribute [IN FRAME frame-name ]

{ FRAME | MENU } widget-name:attribute

{ SUB-MENU | MENU-ITEM } widget-name:attribute    [ IN { MENU | SUB-MENU } menu-name ]

You can chain attribute references. For example, the following attribute reference displays the value of the TITLE attribute for a window containing a fill-in (assuming the fill-in is three levels from the window):

FILL-IN-1:PARENT:PARENT:PARENT:TITLE

If a variable is currently out of scope, or you add a watch for an unknown variable name, the following message appears in the value cell:

** Unavailable **

Double-clicking on a cell containing the value of a variable makes the value editable. You can modify the value by entering a different value and pressing the ENTER key or clicking out of the cell. Pressing the ESC key when editing a value restores the current value and cancels the editing operation.

You can remove a watch for a variable by selecting the watch in the watches pane and then:

Pressing the DELETE key.
Choosing the Remove Watch option on the context (right-click) menu or Debug menu.

Watches for built-in functions

You can add a watch to a built-in 4GL function to track the status of the function.

To add a new watch, type the complete function name directly in the watches pane or choose Debug Add Watch. The Debugger displays the function and its value in the Watches pane.

Table 3–2 lists the 4GL functions supported by the Debugger.

Table 3–2: 4GL functions supported by the Debugger 

Functions that can accept assignment of a new value

Functions that cannot accept assignment of a new value

CURRENT-LANGUAGE PROMSGS PROPATH

_PCONTROL           NUM-ALIASES _SERIAL-NUM         NUM-DBS COM SELF            OPSYS DATASERVERS         OS-DRIVES DBNAME              OS-ERROR ETIME               PROGRESS FRAME-DB            PROVERSION FRAME-FIELD         RETRY FRAME-INDEX         RETURN-VALUE FRAME-NAME          SCREEN-LINES FRAME-VALUE         TERMINAL GO-PENDING          TIME LASTKEY             TODAY MACHINE-CLASS       TRANSACTION MESSAGE-LINES        Note: TERMINAL is settable only on UNIX character interfaces. The values of TIME and TODAY change independently of program execution, so the values displayed in the watches pane might not agree with the last values displayed in the 4GL program.

You can modify a function’s value by editing the value cell in the Watches pane. If the function does not accept an assignment, the function retains its value. In this case, the Debugger does not generate an error message.

Note: You cannot watch a function that requires arguments.

Drag-and-drop watches

You can add a watch by dragging an entity to the watches pane.

To add a watch by dragging and dropping:

Select the text that you want to add a watch for in the source code pane (by clicking and dragging with the mouse to select the text).
Drag the selected text to the watches pane.
Release the mouse button to add the object as a watch to the last (empty) row in the watches pane. If you release the mouse over any other pane or outside the Debugger window, the watch is not added.