Control Structures

As before, an optional number can be given to specify the number of loops to be jumped from, otherwise only the current loop will be aborted. For example:

E> While L=0
    A=0
    Do
     A=A+1
     For X=0 To 100
      Exit If A=10,2 : Rem Exit from DO and FOR loops
     Next X
    Loop
    Exit 1: Rem Exit from WHILE loop
   Wend

Conditional loops

WHILE
WEND
structure: repeat loop while condition is true
While condition
list of statements
Wend

This pair of commands provides a convenient way of making the program repeat a group of instructions all the time a particular condition is true. WHILE marks the start of this loop, and the condition is checked for a value of -1 (True) from this starting position through to the end position, which is marked by a WEND. The condition is then checked again at every turn of the loop, until it is no longer true. For example:

E> BLAZES:
   Print "Please type in the number 9"
   Input X
    While X=9
     Cls : Print X : Wait 50 : Goto BLAZES
    Wend
   Print "That is not a 9!"

You are free to use AND, OR and NOT to qualify the conditions to be checked.

REPEAT
UNTIL
structure: repeat loop until a condition is satisfied
Repeat
list of statements
Until condition