You can make use of several special features to help you type the command line in MM. Most of them are the result of including the CCMD package into MM; CCMD was created at Columbia University to make it easier to type commands.
You can type most MM commands with only one or two letters. For example, at the MM> prompt, r is completed as read, while at the R> prompt, r is completed as reply. Likewise, headers all can be typed as h a, and at the R> prompt reply all including can be typed as r a i.
Default message sequences are added automatically. At the MM> prompt for example, r actually does read unseen.
You can type a partial command or filename and then press the TAB or ESC key to see the completion on screen.
For example, at MM>, type r and then press TAB to see it completed as read (messages). In command completion, anything in parentheses is a suggestion; in this case, it tells you you might want to specify what messages to read. If you then press TAB again, you see unseen, the automatic completion (default) for read. The main reason to use command completion is to get information from MM: to see how it interprets a partially-typed command, or to see what you could type after the command (shown by the suggestion in parentheses). You do not need to use command completion just to give the command, since MM understands partially typed commands.
When you use MM to access an existing file, use completion to avoid typing the full filename. You might be using get or examine to see another mail file, or move or copy to write to another mail file, or using control-b to insert a file into a message, among other things. Type enough of the filename to identify it and then press TAB or ESC to fill in the rest. If it can't find a unique file, it beeps at you. Type ? to see the possible files.
You can also use completion on your own mail-aliases, names of MM variables (with the set or show commands), and your keywords. Try it. It saves lots of typing.
MM remembers commands you have given during the current session (up to a limit), and you can use the history to avoid retyping the same commands.
Control-p displays the previous command. Press control-p until you get back to the command you want to repeat. If you go back too far, control-n moves forward again to the next command.
Following is a simple example. You check headers from howie, looking for a certain old message, and then read 4 thinking message 4 is the one you want. However, message 4 is the wrong one, and by now the headers display has moved off the screen. By using control-p twice, you can get back to the h from howie command, and do it again, using two keystrokes instead of retyping the whole thing.
MM>h from howie [message headers are shown] MM>r 4 [message 4 is shown] MM>[control-p] MM>r 4 MM>[control-p] MM>h