Hi Stefan,
You can skip large blocks of tests coding like this
If Length(txt)>0 then
case txt[1] of
'a': if txt='another' then
...
else if txt='anum' then
...;
'b': if txt="bubble' then
...
else if ...
else
...
end;
Not as fast as a tree search balanced with probabilities (no answer to my question on the list afew days
ago...), but probably ten time faster then what you proposed.
Cheers, Ched'
Le 06.07.2017 à 20:41, Stefan V. Pantazi a écrit :
That is quite the case statement you have there. You may benefit greatly from re-analyzing and
refactoring your programs by splitting them in multiple individual units, if possible. That should be
perfectly possible if Dosomething(); DoSomethingelse(); keep repeating across your 70+ switch cases.
Anyway, here you go, you can try something like the attached.
Good luck!
Stefan
On 07/06/2017 12:33 PM, James Richters wrote:
I'm trying to optimize a console application ported over from Turbo Pascal with a huge set of if then
else statements like this:
Var
TXT : String;
If TXT = 'Thing1' then
Begin
Dosomething();
DoSomethingelse();
End
else
If TXT = 'AnotherThing' then
Begin
Dosomethinganotherway();
DoSomethingelsetoo();
End
Else
If TXT = 'Thing3' then
Begin
Dosomethingathirdtime();
DoSomethingelse3();
End
else .... etc.. over 70 times... etc
It works but it's hard to follow and not so fast. It has to run through this for every line of a file
to see what's in the file and do the right things with it.
So I'm thinking of undertaking a huge re-organization of it and I'm wondering what the best way would
be to do it.
I can use case statement with strings apparently now, but the thing is, I create this file myself in
an earlier stage, so I do not need to create the file with strings at all, I could use some codes and
do something like this:
Const
Thing1 = 1
Another_Thing = 2
Thing3 = 3
Var
Codenum: Word;
Case Codenum of
Thing1: Begin
DoSomethng()
DoSomethingElse()
End;
Another_Thing: Begin
... etc ...
I'm guessing that would be faster as I wouldn't have to keep evaluating all the strings for every
condition. As I was searching for the best way to do this, I came across something about making an
Array of Procedures, or something to that effect. Does anyone know how to do that, and are there
performance advantages to doing that? It's going to take a bit of work to straighten all this out so
it would be best if I just did it the best way instead of doing it one way then finding out it could
have been better another way. Any other ideas on how to handle this?
Any advice on this is greatly appreciated
James
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