### Continuation Line

(Corresponds to Section 3.2.3 of ANSI X3.9-1978 FORTRAN 77.)

A continuation line is any line that both

- Contains a continuation character, and
- Contains only spaces in columns 1 through 5

A continuation character is any character of the GNU Fortran character set
other than space (<SPC>) or zero (`0`

)
in column 6, or a digit (`0`

through `9`

) in column
7 through 72 of a line that has only spaces to the left of that
digit.

The continuation character is ignored as far as the content of
the statement is concerned.

The GNU Fortran language places no limit on the number of
continuation lines in a statement.
In practice, the limit depends on a variety of factors, such as
available memory, statement content, and so on, but no
GNU Fortran system may impose an arbitrary limit.