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MacOS 8.1

Win98

DOS

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+--------+-------------------------+-------------------------+--------+--------+
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|00000d20| 6d 61 6b 65 20 73 75 72 | 65 20 74 68 61 74 20 74 |make sur|e that t|
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|00000d40| 20 69 73 20 70 6f 73 69 | 74 69 76 65 3a 0d 20 20 | is posi|tive:.  |
|00000d50| 49 46 20 70 6f 73 4e 75 | 6d 20 3c 20 30 20 54 48 |IF posNu|m < 0 TH|
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|00000d70| 20 65 72 72 6f 72 21 0d | 20 20 20 20 52 45 54 55 | error!.|    RETU|
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|00000d90| 6c 65 52 65 66 20 3d 20 | 4e 49 4c 20 54 48 45 4e |leRef = |NIL THEN|
|00000da0| 0d 20 20 20 20 2f 2f 20 | 6f 6f 70 73 20 2d 20 61 |.    // |oops - a|
|00000db0| 6e 6f 74 68 65 72 20 65 | 72 72 6f 72 21 0d 20 20 |nother e|rror!.  |
|00000dc0| 20 20 52 45 54 55 52 4e | 0d 20 20 45 4e 44 0d 20 |  RETURN|.  END. |
|00000dd0| 20 2f 2f 20 2e 2e 2e 20 | 67 6f 20 6f 6e 20 77 69 | // ... |go on wi|
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|000029b0| 2d 63 61 6c 6c 65 64 20 | 63 6f 6e 73 74 72 75 63 |-called |construc|
|000029c0| 74 6f 72 3a 0d 20 20 49 | 6e 20 74 68 65 20 4d 79 |tor:.  I|n the My|
|000029d0| 53 70 65 63 69 61 6c 45 | 78 63 65 70 74 69 6f 6e |SpecialE|xception|
|000029e0| 20 61 64 64 20 74 68 69 | 73 20 6d 65 74 68 6f 64 | add thi|s method|
|000029f0| 3a 0d 0d 20 20 20 20 53 | 75 62 20 4d 79 53 70 65 |:..    S|ub MySpe|
|00002a00| 63 69 61 6c 45 78 63 65 | 70 74 69 6f 6e 28 22 6d |cialExce|ption("m|
|00002a10| 73 67 20 61 73 20 53 74 | 72 69 6e 67 22 29 0d 20 |sg as St|ring"). |
|00002a20| 20 20 20 20 20 73 65 6c | 66 2e 6d 73 67 20 3d 20 |     sel|f.msg = |
|00002a30| 6d 73 67 0d 20 20 20 20 | 45 6e 64 20 53 75 62 0d |msg.    |End Sub.|
|00002a40| 0d 20 20 54 68 65 6e 20 | 79 6f 75 20 63 61 6e 20 |.  Then |you can |
|00002a50| 72 61 69 73 65 20 65 78 | 63 65 70 74 69 6f 6e 73 |raise ex|ceptions|
|00002a60| 20 77 69 74 68 20 6d 65 | 73 73 61 67 65 73 20 65 | with me|ssages e|
|00002a70| 61 73 69 65 72 0d 20 20 | 75 73 69 6e 67 20 74 68 |asier.  |using th|
|00002a80| 69 73 20 73 69 6e 67 6c | 65 20 6c 69 6e 65 3a 0d |is singl|e line:.|
|00002a90| 0d 20 20 20 20 52 61 69 | 73 65 20 6e 65 77 20 4d |.    Rai|se new M|
|00002aa0| 79 53 70 65 63 69 61 6c | 45 78 63 65 70 74 69 6f |ySpecial|Exceptio|
|00002ab0| 6e 20 28 22 68 65 72 65 | 20 63 6f 6d 65 73 20 74 |n ("here| comes t|
|00002ac0| 68 65 20 6d 65 73 73 61 | 67 65 22 29 0d 0d 2a 20 |he messa|ge")..* |
|00002ad0| 41 6c 73 6f 20 61 76 61 | 69 6c 61 62 6c 65 20 69 |Also ava|ilable i|
|00002ae0| 6e 20 52 42 20 76 65 72 | 73 69 6f 6e 20 32 20 69 |n RB ver|sion 2 i|
|00002af0| 73 20 61 20 6e 65 77 20 | 75 6e 69 76 65 72 73 61 |s a new |universa|
|00002b00| 6c 20 74 79 70 65 2c 0d | 20 20 63 61 6c 6c 65 64 |l type,.|  called|
|00002b10| 20 61 20 56 61 72 69 61 | 6e 74 2e 20 55 73 69 6e | a Varia|nt. Usin|
|00002b20| 67 20 74 68 61 74 2c 20 | 79 6f 75 20 63 61 6e 20 |g that, |you can |
|00002b30| 6d 61 6b 65 20 74 68 65 | 20 6d 65 73 73 61 67 69 |make the| messagi|
|00002b40| 6e 67 0d 20 20 6d 6f 72 | 65 20 76 65 72 73 61 74 |ng.  mor|e versat|
|00002b50| 69 6c 65 20 62 79 20 63 | 68 61 6e 67 69 6e 67 20 |ile by c|hanging |
|00002b60| 69 74 73 20 74 79 70 65 | 20 66 72 6f 6d 20 53 74 |its type| from St|
|00002b70| 72 69 6e 67 20 74 6f 20 | 56 61 72 69 61 6e 74 2e |ring to |Variant.|
|00002b80| 0d 20 20 54 68 65 6e 20 | 79 6f 75 20 63 61 6e 20 |.  Then |you can |
|00002b90| 70 61 73 73 20 61 6e 79 | 20 62 61 73 69 63 20 74 |pass any| basic t|
|00002ba0| 79 70 65 20 74 6f 20 69 | 74 2c 20 6c 69 6b 65 20 |ype to i|t, like |
|00002bb0| 53 74 72 69 6e 67 73 2c | 20 49 6e 74 65 67 65 72 |Strings,| Integer|
|00002bc0| 73 2c 0d 20 20 42 6f 6f | 6c 65 61 6e 73 20 65 74 |s,.  Boo|leans et|
|00002bd0| 63 2e 0d 0d 54 68 61 74 | 27 73 20 69 74 20 66 6f |c...That|'s it fo|
|00002be0| 72 20 6e 6f 77 2e 20 50 | 6c 65 61 73 65 20 6c 65 |r now. P|lease le|
|00002bf0| 74 20 6d 65 20 6b 6e 6f | 77 20 69 66 20 79 6f 75 |t me kno|w if you|
|00002c00| 20 68 61 76 65 20 61 64 | 64 69 74 69 6f 6e 73 2c | have ad|ditions,|
|00002c10| 0d 63 6f 72 72 65 63 74 | 69 6f 6e 73 20 6f 72 20 |.correct|ions or |
|00002c20| 71 75 65 73 74 69 6f 6e | 73 20 74 6f 20 74 68 69 |question|s to thi|
|00002c30| 73 20 74 65 78 74 2e 20 | 57 72 69 74 65 20 74 6f |s text. |Write to|
|00002c40| 3a 20 72 62 40 74 65 6d | 70 65 6c 2e 6f 72 67 0d |: rb@tem|pel.org.|
|00002c50| 0d 57 72 69 74 74 65 6e | 20 61 6e 64 20 63 6f 70 |.Written| and cop|
|00002c60| 79 72 69 67 68 74 65 64 | 20 62 79 0d 20 20 54 68 |yrighted| by.  Th|
|00002c70| 6f 6d 61 73 20 54 65 6d | 70 65 6c 6d 61 6e 6e 2c |omas Tem|pelmann,|
|00002c80| 20 4d 61 72 63 68 20 31 | 34 2c 20 39 39 0d 00 00 | March 1|4, 99...|
|00002c90| 00 16 00 01 00 00 00 00 | 00 0b 00 09 00 04 00 00 |........|........|
|00002ca0| 00 09 00 00 00 00 00 00 | 00 00 00 30 00 00 00 01 |........|...0....|
|00002cb0| 00 00 00 04 00 00 00 00 | 00 00 00 02 54 45 58 54 |........|....TEXT|
|00002cc0| 00 00 01 00 00 00 00 00 | 00 00 00 00 73 74 79 6c |........|....styl|
|00002cd0| 00 00 01 00 00 00 00 00 | 00 00 00 00 00 00 00 24 |........|.......$|
|00002ce0| 00 00 00 05 00 01 04 07 | 00 3c 00 53 02 9c 02 3c |........|.<.S...<|
|00002cf0| 00 00 00 00 00 00 01 70 | 8c 00 00 00 09 99 91 e0 |.......p|........|
|00002d00| 00 00 00 00 00 00 01 00 | 00 00 2c b2 00 00 2b b2 |........|..,...+.|
|00002d10| 00 00 00 6e 09 75 f7 00 | 33 6a 00 00 00 1c 00 6e |...n.u..|3j.....n|
|00002d20| 00 03 54 45 58 54 00 00 | 00 22 73 74 79 6c 00 00 |..TEXT..|."styl..|
|00002d30| 00 2e 64 72 61 67 00 00 | 00 3a 6b 77 73 74 00 00 |..drag..|.:kwst..|
|00002d40| 00 46 01 00 ff ff 00 00 | 00 00 00 00 00 00 01 00 |.F......|........|
|00002d50| ff ff 00 00 2b 3c 00 00 | 00 00 00 80 ff ff 00 00 |....+<..|........|
|00002d60| 2b 56 00 00 00 00 bf 4c | ff ff 00 00 2b 8a 00 e2 |+V.....L|....+...|
|00002d70| 67 18                   |                         |g.      |        |
+--------+-------------------------+-------------------------+--------+--------+