Editing BASIC09 (section)

===Structured programming===
In addition to the organizational properties of the <code>PROCEDURE</code>, BASIC09 also included a number of extensions to the  [[flow control (data)|flow control]] statements found in BASIC to provide more structure. For instance, the <code>IF</code> statement could be used in the traditional <code>IF</code>...<code>THEN</code> format on a single line, or it could be used in a structured multi-line format:{{sfn|Manual|1984|p=9.4}}

 IF x>10 THEN
   PRINT "x is larger than 10"
 ELSE
  PRINT "x is smaller than 10"
 ENDIF

<code>FOR/NEXT</code> loops naturally have a structured format as the <code>NEXT</code> can be placed on any line, but BASIC09 also added <code>WHILE/ENDWHILE</code> and <code>REPEAT/UNTIL</code> for additional clarity when working with non-indexed loops.{{sfn|Manual|1984|p=9.6-9.7}} It also included the center-exit <code>LOOP/ENDLOOP</code> which used the <code>EXITIF</code> statement for testing anywhere in the loop's body.{{sfn|Manual|1984|p=9.8}}