Re: Chris Sonnack on VB.Net's putative Set statement

From: Programmer Dude (Chris_at_Sonnack.com)
Date: 06/15/04 

Date: Tue, 15 Jun 2004 09:48:04 -0500

Edward G. Nilges writes:

> I found and fixed the problem in the code the same evening it
> was posted without your assistance.

A lie. A bald-faced lie. Which we now expose (again).
Ed, Your Own Words Name You Liar!

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Subject; Re: The Data Quality Act
   Date; Wed, 26 Jun 2002 16:19:37

[Ed posts his C code string tokenizer...]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Subject; Re: The Data Quality Act
   Date; Thu, 27 Jun 2002 15:10:57

I spent a hour or so re-writing the C version to what I would
consider good C practice (and per my own style just for example).
In the process I found a SERIOUS bug in the C code. It occurs on
line 131 of the C text, in the main parse function:
[...]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[Ed still in denial two days later...]

Subject; Re: The Data Quality Act
   Date; Fri, 28 Jun 2002 12:33:39

CS> The allocated string has no room for the trailing nul.

RH> Sorry for missing this during my own review.

EN> You missed it because you know C and it isn't there.

Sorry, Ed, you're in *serious* denial here. There are two major
bugs in your "parsing" function. The first is exactly what I said
it is, and I'll go over it more carefully for you. [..snip...]

> You appear not to have done your homework, for if the bug had been
> in the original it would have blown up immediately, and you did not
> bother to test your proposed code scrap.

Guess what, Ed. I loaded your original, unmodified (mod line wrapping)
source into VC++ and it DOES crash reporting:

    +--------------------------------------------------+
    | DEBUG ERROR! |
    | Program: Test-D.exe |
    | DAMAGE: after Normal block (#40) at 0x00300150 |
    | (Press Retry to debug the application) |
    | |
    | [Abort] [Retry] [Ignore] |
    +--------------------------------------------------+

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[Still swimming in De Nile...]

Subject; Re: The Data Quality Act
   Date; Fri, 28 Jun 2002 18:16:52

> Dude claimed a bug which I have checked out and there is no bug in
> this code:
> [...]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[Finally Ed begins to acknowledge there "may" be a bug...]

Subject; Re: The Data Quality Act
   Date; Fri, 28 Jun 2002 18:24:17

> This MAY be a genuine bug.

No MAY about it.

[...]

> I think having written this that you probably ARE wrong, but I am
> going to take your post home. You were certainly wrong on the null
> length issue and at best are 1 for two down.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[Finally, four days later, Ed acknowledges (NOT FIXES)...]

Subject; Re: The Data Quality Act
   Date; Sun, 30 Jun 2002 23:24:16

> OK. It appears that the malloc needed to malloc one more byte.

Yes.

> Chris is probably one for two since I believe a null string with a
> string delim is handled.

I'm afraid the other bug still exists. It has to do with what happens
with you "parse" a string using string delimiting, but the string has
no delimiter present.

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[Still no acknowledgement of error or simple test cases...]

Subject; Re: The Data Quality Act
   Date; Tue, 09 Jul 2002 17:05:02

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[And STILL not...]

Subject; Re: The Data Quality Act
   Date; Thu, 11 Jul 2002 13:06:19

> I think the problem is that I presented end-to-end solutions which
> worked the first time out,...

No, they didn't. Your C solution crashed immediately and refused
to run until I fixed your error. Even then it produced erroneous
results due to the other bug. That's two major bugs in the single
function of substance in your C solution.

Your VB solution at least runs, but it's poorly designed--particularly
for a tool object. Worse, I say it ALSO produces erroneous results:

For the string: ",Moe,,Larry,Curley,,Shemp,Curley-Joe,CurleyJoeBesser,"

[NOTE: That was YOUR test string, Ed.]

Your VB routine claims there are *nine* tokens. Do you feel there
should be a (blank) token *after* the final comma? That would make
10 tokens...

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[Present day, years later, finally (after asking a dozen times):]

CS> ..how many fields in the following CSV: ",John,,Rogar,Mick,"

EN> There are duh six fields in the string.

Exactly. So why did both your programs report five? 

-- 
|_ CJSonnack <Chris@Sonnack.com> _____________| How's my programming? |
|_ http://www.Sonnack.com/ ___________________| Call: 1-800-DEV-NULL  |
|_____________________________________________|_______________________|

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