manual page: https://www.tcl-lang.org/man/tcl8.6/TclCmd/self.htm
Provides introspection about the currently executing TclOO method. If subcommand is omitted, returns the current name of the object (respecting any renames of it), just as in self object. See https://www.tcl-lang.org/man/tcl8.6/TclCmd/self.htm for details. Supported subcommands are: