Q37319: QB.EXE Editor Fails to Flag Extra ELSE Clause as Syntax Error

Article: Q37319
Product(s): See article
Version(s): 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | buglist4.00 buglist4.00b buglist4.50 | mspl13_basic
Last Modified: 28-DEC-1989

In the program code example below, the QB.EXE environment fails to
detect an extra ELSE clause in an IF statement as being a syntax
error. Instead, the number 0 is displayed as well as number 2.

The BC.EXE compiler successfully flags the extra ELSE clause as a
syntax error. It is logically illegal to use two or more ELSE clauses
in an IF statement. Only one ELSE clause is allowed in an IF
statement. (The ELSE clause can also be left out of an IF statement.)

Microsoft has confirmed this to be a problem in QuickBASIC Versions
4.00, 4.00b, and 4.50. This problem is corrected in the QBX.EXE
environment that comes with Microsoft BASIC PDS Version 7.00
(fixlist7.00).

The following is a code example:

a = 0
IF a = 0 THEN
  PRINT a
ELSE
  PRINT 1
ELSE
  PRINT 2
END IF

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