22.4.15.3 Edebug Recursive Edit

When Edebug is entered and actually reads commands from the user, it saves (and later restores) these additional data:

• The current match data, for whichever buffer was current.
• last-command, this-command, last-command-char, last-input-char, last-input-event, last-command-event, last-event-frame, last-nonmenu-event, and track-mouse . Commands used within Edebug do not affect these variables outside of Edebug.

  The key sequence returned by this-command-keys is changed by executing commands within Edebug and there is no way to reset the key sequence from Lisp.

  For FSF Emacs 18, Edebug cannot save and restore the value of unread-command-char. Entering Edebug while this variable has a nontrivial value can interfere with execution of the program you are debugging.

• Complex commands executed while in Edebug are added to the variable command-history. In rare cases this can alter execution.
• Within Edebug, the recursion depth appears one deeper than the recursion depth outside Edebug. This is not true of the automatically updated evaluation list window.
• standard-output and standard-input are bound to nil by the recursive-edit, but Edebug temporarily restores them during evaluations.
• The state of keyboard macro definition is saved and restored. While Edebug is active, defining-kbd-macro is bound to edebug-continue-kbd-macro.