Q69045: PRINT TAB Blanks Out Passed-Over Characters in BASIC

Article: Q69045
Product(s): See article
Version(s): 2.00 2.01 3.00 4.00 4.00b 4.50
Operating System(s): MS-DOS
Keyword(s): ENDUSER | SR# S910117-30 B_BasicCom B_GWBasicI | mspl13_basic
Last Modified: 6-FEB-1991

BASIC's TAB() function will blank out any characters that are being
passed over on the screen. This feature is by design.

This information applies to Microsoft GW-BASIC versions 3.20, 3.22,
and 3.23; to Microsoft QuickBASIC versions 2.00, 2.01, 3.00, 4.00,
4.00b, and 4.50; to Microsoft BASIC Compiler 6.00 and 6.00b; and to
Microsoft BASIC Professional Development System (PDS) versions 7.00
and 7.10 for MS-DOS.

Consider the following code:

      CLS
      PRINT "1234567890"
      PRINT "abcdefghij"
      LOCATE 2,1
      PRINT TAB(4); "DEF"

This program prints the following on the screen:

      1234567890
         DEFghij

The letters "abc", which TAB passed over, have been overwritten with
blanks.

An exception to this behavior is if you trace (F8) in the QB.EXE
editor of QuickBASIC 4.00, 4.00b, or 4.50, or QBX.EXE of BASIC PDS
7.00 or 7.10, where TAB does not erase passed-over text:

      1234567890
      abcDEFghij

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