WHILE

Parameters

Use HELP FUNCTIONS |OPERATORS |EXPRESSIONS for more info

The WHILE command evaluates expression and displays the result (TRUE or FALSE) to $STDLIST. If expression does not resolve to a Boolean result, an error is reported.

The DO keyword is optional. It may be used or omitted and has no affect on the results.

Operation Notes

This command begins a WHILE block, which consists of all the commands lying between WHILE and the next ENDWHILE statement. The ENDWHILE must have the same nesting level as the WHILE statement. The ENDWHILE statement ends the WHILE block.

The logical expression is evaluated and, as long as expression evaluates to TRUE, the WHILE block is executed.

Nesting of IF and WHILE blocks is limited to a combined total of 30 levels. Each IF or WHILE block read by the Command Interpreter increments the nesting count by 1.

	NOTE: You may not write a WHILE construct in such a way that it physically crosses from one user command (UDCs or command files) to another.

Use

This command may be issued from a session, job, program, or in BREAK. Pressing Break aborts the execution of this command.

Example

The following is an example of the WHILE command:

 WHILE SETVAR (FILENAME, &
    INPUT ("PLEASE ENTER THE NEXT FILENAME TO PURGE:") &
    )<> "" DO
  PLEASE ENTER THE NEXTFILENAME TO PURGE: OLDFILE1
 *** EXPRESSION TRUE
 CONTINUE
 PURGE !FILENAME
 ENDWHILE