Loops

RCBasic provides three types of loops: For, While, and Do.

For Loop

Repeats a block a fixed number of times, incrementing a counter variable each iteration.

  For I = 1 To 5
    Print I
Next
' Output: 1 2 3 4 5

Use Step to change the increment amount:

  For I = 1 To 5 Step 2
    Print I
Next
' Output: 1 3 5

Step can also be negative to count down:

  For I = 10 To 1 Step -1
    Print I
Next

While Loop

Executes a block of code while a condition remains true. The condition is tested before each iteration, so the body may never execute if the condition is false from the start.

  I = 0
While I < 5
    Print I
    I = I + 1
Wend
' Output: 0 1 2 3 4

Warning

Make sure the loop variable changes inside the loop body, otherwise you will create an infinite loop.

Do Loop

Similar to While, but the condition is checked after the body executes. This guarantees the body runs at least once.

The Do loop has three forms:

Infinite loop

  Do
    Print "HELLO WORLD"
Loop
' Runs forever — use Exit to break out.

Loop While (continue while true)

  I = 0
Do
    Print I
    I = I + 1
Loop While I < 5
' Output: 0 1 2 3 4

Loop Until (continue until true)

  I = 0
Do
    Print I
    I = I + 1
Loop Until I = 5
' Output: 0 1 2 3 4

Summary

Loop	Condition checked	Best used when
`For`	Start (count-based)	You know the exact number of iterations.
`While`	Start	You need to check a condition before the first run.
`Do`	End	The body must always execute at least once.