DO

Initiates a conditional loop, whose condition is to be evaluated at the end of each pass

Implemented by:

With variations:

Also written as:

Usage

DO is a quite generic word, but in BASIC it is mainly used with loop structures — yes, more than one.

It can be used in a DO…LOOP without a condition, and the block of commands is repeated until an EXIT is found:

  110 DO
  ...  ' whatever commands here   
  150 LOOP

For running the loop while and only if a condition evaluates to Boolean true, there is the DO WHILE…LOOP:

  110 DO WHILE A <= 100
  120   A = A + 1
  130   DIF = DIF + 1   
  140 LOOP

Sometimes you'd want a block to execute at least once and repeat while a condition is not met. You will appreciate the DO… LOOP UNTIL structure:

  110 DO 
  120   A = A + 1
  130   DIF = DIF + 1   
  140 LOOP UNTIL A = 100