All advanced Basic programs have a GOTO statement.

• a FOR-NEXT checks the condition at the beginning and if false GOTOs the instruction after the NEXT, which itself is replaced with a GOTO to the loop condition check at the beginning of the loop;
• a LOOP-WHILE/UNTIL_cond_DO-REPEAT becomes a IF THEN GOTO at the WHILE/WHILE statement, going to the instruction after the REPEAT, which itself becomes a GOTO the LOOP keyword (which itself is actually just removed from the byte code) [jumping in/out of LOOP...REPEAT blocks is very nasty coding but will compile to perfectly legal byte code and causes no memory problems];
• IF-THEN-ELSE becomes IF false GOTO "else" block followed by the "then" block which is ended by a GOTO end of "else" block, followed by the "else" block.

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• You have been a great comfort to me. ...nt - Authored by: Ian Al on Saturday, May 19 2012 @ 11:54 AM EDT