Important Notice
The pages on this site contain documentation for very old MS-DOS software,
purely for historical purposes.
If you're looking for up-to-date documentation, particularly for programming,
you should not rely on the information found here, as it will be woefully
out of date.
Key (↑ Statements)
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Dialects
The syntax diagrams in the On-line Reference contain full syntax
for all dialects. However, there is no indication of dialect on
syntax diagrams.
For full details of dialects and a full definition of the COBOL
syntax please refer to your COBOL Language Reference.
Railroad Tracks
COBOL syntax is shown using diagrams called "railroad tracks", in
which the words and phrases comprising a construct are shown
joined by lines indicating the order they should be written in.
You read these diagrams left-to-right. Each diagram starts with
►► and ends with ►◄.
Sometimes the track forks to show alternatives and then joins up
again. An arrow starting after a word or phrase and pointing back
before it, forming a loop, means it can be repeated. The length
of a track has no significance.
When a diagram reaches the right-hand side of the screen, it is
continued further down. A track continued onto a new line ends
with ►, and the new line begins with ►. If several tracks are
continued they are numbered so you can match up each track with
its continuation.
Within the diagrams, COBOL reserved words which are not significant
and can be left out without affecting the sense of the statement
(noise words) are indicated by a "drop-out" with narrow sides.
Reserved words which are optional, but change the sense of the
statement when included are shown by a drop-out with wide sides.
For example, in the statement:
►►──GET─┬───┬─SYNTAX─┬───────────┬────►◄
└NEW┘ └─BACKWARDS─┘
the word NEW can be left out without affecting the operation.
However, omitting the the word BACKWARDS will produce a different
effect than if it is included.
Multiple Formats
Many COBOL statements have several alternative formats. When you
enter the topic for such a statement, the format displayed under
the "Syntax" heading is the one most commonly used. There is a
format selector consisting of a button for each format; when you
select a button, the format displayed changes to the one you
have chosen. The button for the format currently displayed is
highlighted.
Within a format, all options are shown. There is no indication of
which dialect each option belongs to. To distinguish dialects,
see the ◄FLAG► directive.
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