Re: [Xenocide-programming] always PAQ

[<fl...@ma...>]

Dont worry about optimizing it too much, I am more interested to make =
sure it works how it is supposed to work. And move to another task, we =
can always profile and optimize later... 1% of the code gets you 99% of =
the bang. The other important stuff to consider is code readability, I =
didnt have much problem to understand it, however there are still some =
deviations from the coding standard that you had followed almost =
flawlessly in this version of the code...

The use of the { in an improper place like in the virtual file like this

 switch (startingPoint){

 // If invalid value, assume default and continue
 default:
  advAssert(0,"Unknown starting point. _STINITIALPOSITION assumed");
};

It should be like this:

switch (startingPoint)
{

 // If invalid value, assume default and continue
 default:
    {
       advAssert(0,"Unknown starting point. _STINITIALPOSITION =
assumed");
    }
};

By the way try not to use the switch continuation unless you really need =
to, the semantics of that structure is pretty difficult to follow for =
non seasoned C++ programmers. And it is easy to overlook its =
implications when debugging.

Ex:

switch (pepe)
{
case 1:
    { pepe--; };
case 2:=20
    {
        pepe++;=20
        break;
    };
};

I had saw too some unneeded uses of the continue keyword at the =
paqdeveloperstable.cpp file..
Ex:
 // Binary search
 while(max >=3D min)
 {
  mid=3Dmin + (max-min)/2;

  if ( mid->filenameHash =3D=3D crcNumber )
  {
   this->namesList.erase(mid);
   return;
  }
  else if (mid->filenameHash > crcNumber)
   { max =3D mid-1; continue; } // sx
  else=20
   { min =3D mid+1; continue; } // dx
 }

It should be:

 // Binary search
 while(max >=3D min)
 {
  mid=3Dmin + (max-min)/2;

  if ( mid->filenameHash =3D=3D crcNumber )
  {
   this->namesList.erase(mid);
   return;
  }
  else if (mid->filenameHash > crcNumber)
   { max =3D mid-1; } // sx
  else=20
   { min =3D mid+1; } // dx
 }

As stated above try to avoid using that kind of dynamic semantic rules =
(they are hidden gotos) that make pretty difficult the readability of =
the code... Read this as: "If there is another way to do it (more =
clearly) use it, if not we will have to live with that".

About the library stuff, dont worry I will do that personally. And no, =
we dont need a command line utility, that is what PAQ Explorer is for. =
About the PAQ Explorer if anyone reading this mail wants to take that =
task, you are welcome to raise your hand... By the way if you never used =
VCL it is not difficult at all (promise), in fact it is the easies way =
arround any GUI related programming problem, if you have a GUI to do in =
C++ consider use Borland to do that. It is amazing what it can do, by =
the way if you already know Delphi, it is the same library :D=20

Greetings
Red Knight
  ----- Original Message -----=20
  From: Ermete Gaudenzi=20
  To: xen...@li...=20
  Sent: Saturday, July 19, 2003 7:01 PM
  Subject: Re: [Xenocide-programming] always PAQ


  Hi to all again.

  I've finished the PAQ Manager implementation. YEP!
  Now I'm going to review the code, optimize it, comment it better and =
so on..
  Today I finally finished the developers table manager and I improved =
the speed in the addFile methods.
  I changed the insertion algorithm from -append to the end then sort =
all- into -binary search the right place and insert there-.
  The code is a bit more difficult to understand but the speed is really =
better !!
  I tried to add the entire filenames of my hard disk into the archive =
with full path (of course without the real file data). There was 19079 =
files... whoops
  Elapsed time: 32927 milli-seconds
  I'm impressed... and I run the test in debug mode... let's try in =
release speed-optimized mode...
  Elapsed time: 24466 milli-seconds
  Even better !!! It's near the 1-file-per-millisecond limit :-))
  This of course adding the file data (1byte), file descriptor and =
filename.

  Future issues are:
  - more comments and cleaner code
  - improve the error handling (currently it's poor)
  - make it a library instead of a class (ouch... I can't do this for =
now since I don't have the BCB)
  - writing a test utility (the one I used is not serious)
  - writing a command-line utility (really needed?)
  - writing the PAQ Explorer. I never worked with GUI so I may not be =
the right person doing it

  I suggest to do not put this code in the CVS yet, it's better to wait =
until at least the error handling has become serious.
  I updated the task in sourceforge, incremented % complete to 70%
  In the attached code I included the test utility... just for who is =
curious. Anyway that is really a mess, so be careful to don't gain a =
head ach reading it !!

  Critics and comments are *ALWAYS* wellcome.

  regards
  exio82=20


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