jsdIExecutionHook Interface

 Hook instances of this interface up to the
 jsdIDebuggerService::breakpointHook, debuggerHook, errorHook, interruptHook,
 and throwHook properties.


 TYPE_* values must be kept in sync with JSD_HOOK_* #defines in jsdebug.h.


 Execution stopped because we're in single step mode.

const unsigned long TYPE_INTERRUPTED = 0

 Execution stopped by a trap instruction (i.e. breakoint.)

const unsigned long TYPE_BREAKPOINT = 1

 Error handler returned an "invoke debugger" value.

const unsigned long TYPE_DEBUG_REQUESTED = 2

 Debugger keyword encountered.

const unsigned long TYPE_DEBUGGER_KEYWORD = 3

 Exception was thrown.

const unsigned long TYPE_THROW = 4

 RETURN_* values must be kept in sync with JSD_HOOK_RETURN_* #defines in
 jsdebug.h.


 Indicates unrecoverable error processing the hook.  This will cause
 the script being executed to be aborted without raising a JavaScript
 exception.

const unsigned long RETURN_HOOK_ERROR = 0

 Continue processing normally.  This is the "do nothing special" return
 value for all hook types *except* TYPE_THROW.  Returning RETURN_CONTINUE
 from TYPE_THROW cause the exception to be ignored.  Return
 RETURN_CONTINUE_THROW to continue exception processing from TYPE_THROW
 hooks.

const unsigned long RETURN_CONTINUE = 1

 Same effect as RETURN_HOOK_ERROR.

const unsigned long RETURN_ABORT = 2

 Return the value of the |val| parameter.

const unsigned long RETURN_RET_WITH_VAL = 3

 Throw the value of the |val| parameter.

const unsigned long RETURN_THROW_WITH_VAL = 4

 Continue the current throw.

const unsigned long RETURN_CONTINUE_THROW = 5