READLIST

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The READLIST statement reads a select list into a dynamic array.

 

 

Format

 

READLIST var {FROM list.no}

{THEN statement(s)}

{ELSE statement(s)}

 

where

 

varis the variable to receive the select list.

 

list.nois the select list number. If omitted, select list zero is used.

 

statement(s)are statement(s) to be performed depending on the outcome of the READLIST operation.

 

At least one of the THEN and ELSE clauses must be present.

 

The specified select list is read into var. If the list had already been partially processed by READNEXT statements, only the remaining unprocessed items are stored in var.

 

The select list is empty after the READLIST statement is completed.

 

The THEN clause is executed if var contains one or more items. Items are separated by field marks. If compatibility with other software is required, it is suggested that programs should be written to accept either field marks or item marks (or a mix) as list separators.

 

The ELSE clause is executed if the select list was not active or if no items remained to be processed. In this case var will be set to a null string.

 

 

Example

 

READLIST S FROM 2 THEN

  WRITE S TO LISTS, "UNPROCESSED"

END

 

This program fragment retrieves the remaining items in select list 2 and, if there are any, writes them to a record UNPROCESSED in file LISTS.