A Cmd instance has the following methods:
The optional argument is a banner or intro string to be issued before the first prompt (this overrides the intro class member).
If the readline module is loaded, input will automatically inherit bash-like history-list editing (e.g. Control-P scrolls back to the last command, Control-N forward to the next one, Control-F moves the cursor to the right non-destructively, Control-B moves the cursor to the left non-destructively, etc.).
An end-of-file on input is passed back as the string
An interpreter instance will recognize a command name "foo" if and only if it has a method do_foo(). As a special case, a line beginning with the character "?" is dispatched to the method do_help(). As another special case, a line beginning with the character "!" is dispatched to the method do_shell() (if such a method is defined).
If completion is enabled, completing commands will be done automatically, and completing of commands args is done by calling complete_foo() with arguments text, line, begidx, and endidx. text is the string prefix we are attempting to match: all returned matches must begin with it. line is the current input line with leading whitespace removed, begidx and endidx are the beginning and ending indexes of the prefix text, which could be used to provide different completion depending upon which position the argument is in.
All subclasses of Cmd inherit a predefined do_help().
This method, called with an argument
'bar', invokes the
corresponding method help_bar(). With no argument,
do_help() lists all available help topics (that is, all
commands with corresponding help_*() methods), and also lists
any undocumented commands.
Instances of Cmd subclasses have some public instance variables: