A method, apparatus, system, and signal-bearing medium that in an
embodiment create breakpoint groups and breakpoints in a hierarchical
tree structure. An operation directed to a breakpoint group is performed
on both the breakpoint group and the descendents in the tree of the
breakpoint group. But, an operation directed to a descendent is not
performed against its ancestors. In this way, the user can ore easily
organize, enable, and disable breakpoints.