ugBASIC User Manual

   DO
     ... instructions ...
   LOOP

Repeats a block of statements. Use a DO…LOOP structure when you want to repeat a set of statements an indefinite number of times, or until an EXIT control out of the loop. If you want to repeat the statements a set number of times, the FOR…NEXT statement is usually a better choice, while if you want to repeat for specific conditions, you should use the WHILE…WEND' and REPEAT…UNTIL statements.

The DO…LOOP structure gives you less flexibility than the WHILE / UNTIL statements because you cannot decide whether to end the loop when a specific condition stops being TRUE or when it first becomes TRUE. It also disallow you to test condition at either the start or the end of the loop. You can nest DO…LOOPS by putting one loop within another. You can also nest different kinds of control structures within each other.

  DO
    x = x + 1
  LOOP

See also the following example files:

• control_loops_01.bas
• control_loops_02.bas
• control_loops_03.bas
• control_loops_04.bas
• control_loops_05.bas

 Do...Lp

• Atari (400/800)
• Atari XL/XE
• Commodore 128 (MOS 8502)
• Commodore 128 (Zilog Z80)
• Commodore 64
• Commodore 64+REU
• TRS-80 Color Computer
• TRS-80 Color Computer 3
• ColecoVision
• Amstrad CPC 664
• Dragon 32
• Dragon 64
• Thomson MO5
• Thomson MO5
• Olivetti Prodest PC128
• Commodore PLUS/4
• SEGA SC-3000
• SEGA SG-1000
• VG-5000
• Commodore VIC-20
• ZX Spectrum 48

If you have encountered a problem using this command, if you think there is a bug or the explanation is unclear, please open an issue for this keyword on GitHub. Thank you!