Simple repetitive loops can be run a number of times. You can specify the number of repetitions for the loop, or you can use a variable that has a changing value.
The following shows how to repeat a loop a fixed number of times.
DO num instruction1 instruction2 instruction3 ... END
The num is a whole number, which is the number of times the loop is to be run.
Here is LOOP.CMD, an example of a simple repetitive loop.
/* A simple loop */ DO 5 SAY 'Thank-you' END EXIT
When you run the LOOP.CMD, you see this on your screen:
[C:\]loop Thank-you Thank-you Thank-you Thank-you Thank-you [C:\]
Another type of DO instruction is:
DO XYZ = 1 to 10
This type of DO instruction numbers each pass through the loop so you can use it as a variable. The value of XYZ changes (by 1) each time you pass through the loop. The 1 (or some number) gives the value you want the variable to have the first time through the loop. The 10 (or some number) gives the value you want the variable to have the last time through the loop.
NEWLOOP.CMD is an example of another loop:
/* Another loop */ sum = 0 DO XYZ = 1 to 7 SAY 'Enter value' XYZ PULL value sum = sum + value END SAY 'The total is' sum EXIT
Here are the results of the NEWLOOP.CMD procedure:
[C:\]newloop Enter value 1 2 Enter value 2 4 Enter value 3 6 Enter value 4 8 Enter value 5 10 Enter value 6 12 Enter value 7 14 The total is 56 [C:\]
When a loop ends, the procedure continues with the instruction following the end of the loop, which is identified by END.