Ahh but are we talking 'efficiency' or 'code speed'? what about 'code size'
Just stirring 8-) Neven ----- Original Message ----- From: "David Brennan" <[EMAIL PROTECTED]> To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> Sent: Friday, October 31, 2003 2:01 PM Subject: RE: [DUG]: Just wondering... > On the contrary, I believe the concensus was that it would probably be more > efficient to use ItemIndex = 1 for the first label and then look at the > enabled properties from there. > > And yes, the most efficient option (even more efficient than the two options > you considered) is to use a local boolean variable. > > As some people have pointed out, chances are the difference in speed will be > negligable unless you are doing this in a fairly tight loop. > > David. > > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] > > Behalf Of Ross Levis > > Sent: Friday, 31 October 2003 1:49 PM > > To: Multiple recipients of list delphi > > Subject: Re: [DUG]: Just wondering... > > > > > > Hi Dennis (and others) > > > > So I presume you are suggesting the more efficient way is to repeat the > > itemindex = 1 expression. > > > > Options is usually a radio group, but sometimes it's a checkbox and using > > the checked property instead of itemindex = 1. > > > > Often it is more than 2 components I want enabled/disabled based on the > > Options selection. There can be 6 for example, which is why I was > > interested to know the best way of coding it. Not that the speed > > difference > > would be noticeable but if one is more efficient than the other > > then why not > > use it from now on. > > > > Is it more efficient to store the value in a local boolean variable before > > applying to several components? > > > > Regards, > > Ross. > > > > ----- Original Message ----- > > From: "Dennis Chuah" <[EMAIL PROTECTED]> > > To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> > > Sent: Friday, October 31, 2003 1:11 PM > > Subject: Re: [DUG]: Just wondering... > > > > > > > > > > Actually, this is a misconception. The compiler cannot fold the code > > > because Option.ItemIndex accesses a property, which translates > > to a method > > > call, and therefore can have side-effects. (Yes folks, all property > > > accesses are method calls, even if no accessor methods are > > defined and the > > > property points directly at a variable.) So, if the optimiser were to > > fold > > > the code, you would only get one method call instead of two! The only > > time > > > when code is folder (and it is not even guaranteed), is when > > you directly > > > access variables. > > > > > > ----- Original Message ----- > > > From: "Rohit Gupta" <[EMAIL PROTECTED]> > > > To: "Multiple recipients of list delphi" <[EMAIL PROTECTED]> > > > Sent: Friday, October 31, 2003 12:07 PM > > > Subject: Re: [DUG]: Just wondering... > > > > > > > > > > First because the compiler should detect it and fodl the code. > > > > > > > > Second because it uses less cpu cycles. > > > > > > > > :-) > > > > > > > > I normally use a local variable to hold teh value with a name that > > > > tells the world what it means. Or > > > > > > > > if Option.ItemIndex = 1 > > > > then begin > > > > end > > > > else begin > > > > end > > > > > > > > > > > > > > Which of the following codeis the most efficient/fastest to execute? > > > > > > > > > > Label1.Enabled := Option.ItemIndex = 1; > > > > > Label2.Enabled := Option.ItemIndex = 1; > > > > > > > > > > or > > > > > > > > > > Label1.Enabled := Option.ItemIndex = 1; > > > > > Label2.Enabled := Label1.Enabled; > > > > > > > > > > Thanks, > > > > > Ross Levis. > > > > ------------------------------------------------------------------ > > --------- > > New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] > > Website: http://www.delphi.org.nz > > To UnSub, send email to: [EMAIL PROTECTED] > > with body of "unsubscribe delphi" > > Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/ > > -------------------------------------------------------------------------- - > New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] > Website: http://www.delphi.org.nz > To UnSub, send email to: [EMAIL PROTECTED] > with body of "unsubscribe delphi" > Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/ > > > --------------------------------------------------------------------------- New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED] Website: http://www.delphi.org.nz To UnSub, send email to: [EMAIL PROTECTED] with body of "unsubscribe delphi" Web Archive at: http://www.mail-archive.com/delphi%40delphi.org.nz/
