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8.15 REREAD

REREAD [FILE=handle] [COLUMN=column] [ENCODING=’encoding’].

The REREAD transformation allows the previous input line in a data file already processed by DATA LIST or another input command to be re-read for further processing.

The FILE subcommand, which is optional, is used to specify the file to have its line re-read. The file must be specified as the name of a file handle (see File Handles). If FILE is not specified then the last file specified on DATA LIST is assumed (last file specified lexically, not in terms of flow-of-control).

By default, the line re-read is re-read in its entirety. With the COLUMN subcommand, a prefix of the line can be exempted from re-reading. Specify an expression (see Mathematical Expressions) evaluating to the first column that should be included in the re-read line. Columns are numbered from 1 at the left margin.

The ENCODING subcommand may only be used if the FILE subcommand is also used. It specifies the character encoding of the file. See INSERT, for information on supported encodings.

Issuing REREAD multiple times will not back up in the data file. Instead, it will re-read the same line multiple times.