COBOL Program Standard

Updtaed 2009.02.22

The purpose of a program standard is to make it easier to understand programs, to develop coding techniques that reduce the complexity of programs, and to control the entire software development effort. The following guidelines are adapted from the book COBOL With Style by Henry Ledgard.

FILES

· With our compiler, Cobol files always have the extension “.cbl”.

· In this class, data files will always have the extension “.txt”.

· In this class, “printer” files will always have the extension “.prn”.

· In this class, error files will always have the extension “.err”.

· Always turn in hard copies of your "cbl", "prn", and "err" files.

· Always print your full name as the first line of all output files (both prn and err).

GENERAL RULES

• Between each division, section, or paragraph, there must be a page eject or a sequence of blank lines that is longer than the maximum sequence of blank lines within the previous division, section, or paragraph. (e.g. use 3 blank lines between divisions, 2 blank lines between sections, and 1 blank line between paragraphs)
• Place division headers, section headers, and paragraph names on lines by themselves.
• Do not break words or numeric constants across lines.
• Begin every comment line with "***".
• Continuation lines must be indented at least two spaces from the starting position of the previous line.

IDENTIFICATION DIVISION.

• Always include the following paragraphs:

Author.
Program-ID.

• Always include comments that give a brief description of the program's purpose, the required inputs, and the expected outputs.

DATA DIVISION.

• All data items that remain constant throughout a program must be initialized in a VALUE clause. Use the traditional convention of using all caps for names of constants.
• Start level indicators (FD, SD, CD, RD) and 01 level numbers at column 10.
• The level numbers of immediately subordinate items of a group item must be indented at least two spaces (four would be better) from the starting position of the level number of the group item.
• In an FD, SD, CD, or RD entry with multiple clauses, place each clause on a separate line, indenting each clause at least two spaces from the starting position of the entry name.

PROCEDURE DIVISION.

• The maximum length of a paragraph is one page.
• GO TO statements are not allowed.
• Use the COMPUTE verb for arithmetic computations.
• Begin each statement on a new line.
• Align the starting positions of the statements making up a sentence and the sentences making up a paragraph. The general rule is to align logically parallel constructs.
• The word ELSE should be aligned with the corresponding word IF. The statements in the IF part and the ELSE part must be indented at least two spaces.
• Place phrases such as AT END, WHEN, INVALID KEY, GIVING, USING, TALLYING, VARYING, UNTIL, and AFTER on separate lines, indenting the start of each phrase at least two spaces to the right.