HELP VEDINASCII                                   A. Sloman, Apr 1986
                                          Revised: Nic Ford, Jul 1987
                                          Revised: Dan Perri,Aug 1989

    vedinascii() -> <character>

This is the character repeater procedure used by the VED editor to read
characters (supposedly) typed into the terminal by the user. The
character code -vedinascii- returns is derived in the following way:

    a)  If -ved_char_in_stream- is an empty list, then
        -vedscr_read_ascii- is called to read a character from the
        keyboard.

    b)  If -ved_char_in_stream- is a non-empty list, and its first
        element is a character, then this element is removed and
        returned as the required character.

    c)  If -ved_char_in_stream- is a non_empty list, and its first
        element is a string, then this string is removed and
        converted into a list of characters (which is added to the
        front of -ved_char_in_stream-), and step (b) is repeated.

    d)  If -ved_char_in_stream- is a non_empty list, and its first
        element is a procedure, then it is ignored.


Steps (b) and (c) provide a mechanism which allows VED procedures to
simulate input typed by the user, e.g. as a way of defining new
abbreviations.

See also
    REF *VEDPROCS   - list of the main ved procedures
    HELP *CHARIN    - reads from the terminal outside VED
    HELP *RAWCHARIN - reads from the terminal in "raw" mode.
    HELP *VEDINPUT  - puts items on VED_CHAR_IN_STREAM


--- C.all/help/vedinascii ----------------------------------------------
--- Copyright University of Sussex 1989. All rights reserved. ----------
