Main Help → GENerel Reference → Repeat Loops

Repeat Command

The Repeat command can be used to set up loops in the commands. The format for repeat loops, which may be nested, is:

Repeat "#x",start,end,<step>
  (commands in the loop)
    ...
  break
    ...
  Repeat "#y",start,end,<step>
    (commands in nested loop)
      ...
    continue
      ...
    Repeat
      (commands in nested continuous loop)
        ...
      breakAll
        ...
    EndRepeat
  EndRepeat
EndRepeat

where

• Repeat "#x",start,end,step
  This command sets up a repeat loop. The first argument is a reference to the repeat variable (i.e quoted variable name or an expression that evaluates to a variable name). The following three arguments give the starting and ending values for the loop and the step size to increment the value each pass through the loop. If the step size is not included, it is set to 1. Negative step sizes are allowed. A loop may have zero passes if start is greater than end (for positive step size) or less then end (for negative step size).
• A Repeat with no variables will loop forever. It will cause an endless loop unless some condition within the loop forces a break.
• A break can be used in any loop. It will exit the current loop. If there are nested loops, control will enter the next higher loop.
• A breakAll can be used in any loop. It will exit all current loops and pass control to after the last EndRepeat command.
• A continue command will increment the current loop variable and go back to the start of that loop. If the loop is done, it will exit.

Notes

1. You cannot permanently change the loop variable during a loop. If you change it, it will be reset to the next loop value at the start of the next pass through the loop. For example:

   Repeat "#x",1,5
     Write #x
     #x+=10
   EndRepeat
   

   will write 1,2,3,4,5 on successive lines even though #x was changed in the loop. Each pass through the loop resets #x to the next loop value.