During the backtrace after an error message, a position in interpreted code is displayed and the debugger is entered only if the load depth was at least as large at the time the code was parsed as the error depth is now. The default value is 3, which shows only positions in the user's code and positions inside loaded packages whose debugging mode is true. Set it to 2 to also debug statements inside loaded packages, except for the package Core. Set it to 1 to also debug statements in the core, and set it to 0 to debug statements in the bootstrap code.
The object errorDepth is an integer.