This compiler error will occur if the range used with an in operator is incorrect.

bIsWeekend = (nWeekday in [7..6]) // reverse order

Note that this message can also occur, under the same circumstances if the range used in a case statement is incorrect.

switch nWeekday
   case 1..5 {this is OK}
      sRESULT = 'Working Day'
   case 7..6 // reverse order
      sRESULT = 'Weekend'
endswitch

Use [6..7] to include both 6 and 7. The lower endpoint belongs first; both endpoints are included.

See the topic on the range operator for the rules on range construction.

Topic 109005, last updated on 16-Oct-2026