Notation for this reference

    default values          : 1
    <*>                     : `*' must not be taken literally
    [*]                     : `*' is optional
    ^X                      : <ctrl-X>
    <sp>                    : Space
    <cr>                    : Carriage return
    <lf>                    : Linefeed
    <ht>                    : Horizontal tab
    <esc>                   : Escape
    <erase>                 : Your erase character
    <kill>                  : Your kill character
    <intr>                  : Your interrupt character
    <a-z>                   : An element in the range
    N                       : Number (`*' = allowed, `-' = not appropriate)
    CHAR                    : Char unequal to <ht>|<sp>
    WORD                    : Word followed by <ht>|<sp>|<lf>