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HELP DO                                Updated A.Sloman, Aug 1988


This is a syntax word intended for use with a range of looping
constructs, e.g.

    until <condition> do <actions> enduntil
    while <condition> do <actions> endwhile
    for <var> in <list> do <actions> endfor


In an early version of POP-11, "DO" was a synonym for "THEN", and as a
result there are still some programs using "DO" in conditionals. For
upward compatibility this flexibility has been maintained, though
opinions differ as to whether the use of "DO" in conditional imperatives
should be encouraged.

There is also a VED <ENTER>do command described in
    HELP * VEDCOMMS/ved_do

See also HELP
    *CONTROL      - summary of control facilities in Pop-11
    *CONDITIONALS - summary of conditional statements, all using THEN
    *LOOPS        - summary of iterative constructs, many using DO
    *FOR          - overview of "for" loops
    *UNTIL        - use of iterative construct UNTIL
    *WHILE        - use of iterative construct WHILE
    *THEN         - use of syntax word THEN in conditionals


--- C.all/help/do ------------------------------------------------------
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