zap-to-char function uses the
This function clips text from a region and copies that text to
the kill ring, from which it may be retrieved.
The Emacs 21 version of that function uses
copy-region-as-kill, both of which we will explain.
condition-case is an important special form.
In essence, the
kill-region function calls
condition-case, which takes three arguments. In this function,
the first argument does nothing. The second argument contains the
code that does the work when all goes well. The third argument
contains the code that is called in the event of an error.