The Source Debugger enables you to set a conditional watch using an expression. To do so:
Select the watch tab to which you wish to add the watch. (There are four watch tabs situated below the watch window.)
Click the Add Watch button. A field will open on the selected watch tab to allow you to enter the expression to be watched.
Enter an expression (e.g. \I + 42).
Press the Enter key. The expression will be added to the selected watch tab.
Note: You must use the scope resolution operator (\) at the beginning of the expression, or an "unknown variable or function" error will result.