Syntax: Exec
Abbreviation: EX
prompts the user on the input line, asking for a command, and executes it. It is never registered while recording a macro (though the command you type is).
Exec is mainly useful for key bindings, menu configurations, and in
manually programmed macros.
Note that if the command you specify does not appear in ne’s internal
tables, it is considered to be a macro name. See Macro.