FOR Loops¶
For loops are a little different than do-loops. For loops were created with the purpose in mind of having a program execute between a range. That range is defined by you!
Here’s an example that counts from 0 to 10:
1 2 3 4 5 6 7 | x VAR WORD
Main:
FOR x = 0 TO 10
DEBUG DEC ? x, CR
NEXT
END
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By default, a FOR loop will step through 1 by 1. We can change this behavior by adding a specific value for STEP.
Here the example counts from 0 to 10 but increasing by STEPS of 2:
1 2 3 4 5 6 7 | x VAR WORD
Main:
FOR x = 0 TO 10 STEP 2
DEBUG DEC ? x, CR
NEXT
END
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Notice how only even numbers are being displayed!
We can also make a FOR loop that decreases in range. Here’s what I mean:
1 2 3 4 5 | Main:
FOR 10 TO 5
DEBUG "Hello!"
NEXT
END
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Conclusion¶
FOR loops are very useful when you know there should be a range where a program should run. If we need to run something 10 times then it would be useful to use a FOR loop as its easy to create.
Take this for example, printing 1 to 10 by hand:
1 2 3 4 5 6 7 8 9 10 11 12 | Main:
DEBUG "1"
DEBUG "2"
DEBUG "3"
DEBUG "4"
DEBUG "5"
DEBUG "6"
DEBUG "7"
DEBUG "8"
DEBUG "9"
DEBUG "10"
END
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VS
Printing 1 to 10 using a for loop:
1 2 3 4 5 6 7 | x VAR WORD
Main:
FOR x = 1 to 10
DEBUG DEC x
NEXT
END
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