Tab Form

The tab form source text is defined as follows:

• A tab in any of columns 1 through 6 makes the line as a tab form source line.

• A comment indicator or a statement number may precede the tab.

• If a tab is the first nonblank character, then:

  • If the character after the tab is anything other than a nonzero digit, then the text following the tab is an initial line.

  • If there is a nonzero digit after the first tab, the line is a continuation line. The text following the nonzero digit is the next part of the statement.

• The default maximum line length is 72 columns for fixed form and 132 for free form.

Example: The tab form source on the left is treated as shown on the right.

!^IUses of tabs
^ICHARACTER *3 A = 'A'
^IINTEGER B = 2
^IREAL C = 3.0
^IWRITE(*,9) A, B, C
9^IFORMAT(1X, A3,
^I1 I3,
^I2 F9.1 )
^IEND
!       Uses of tabs
        CHARACTER *3 A = 'A'
        INTEGER B = 2
        REAL C = 3.0
        WRITE(*,9) A, B, C
9       FORMAT(1X, A3,
       1 I3,
       2 F9.1 )
        END

In the example above, "^I" is a way of indicating the tab character, and the line starting with "1" and "2" are continuation lines. The coding is shown to illustrate various tab situations, and not to advocate any one style.