reversing the comparison
in [Visual Basic]
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From: Dee Earley on 20 Jul 2010 05:04 On 20/07/2010 02:48, Karl E. Peterson wrote: > But what if the function has eight or nine parameters, and you end up with: > > If SomeFunction(Byval aLongVarName, ByVal SomeMoreData, ByVal Blah, > By<clipped> > > Are you testing for true or false? If you put the False up front, it's > really clear when you make an exception to the normal situation. I'd use: If Not SomeFunction(... On looking through my own project, the only occurance of "If blah = False" is your FindWindowList module :) -- Dee Earley (dee.earley(a)icode.co.uk) i-Catcher Development Team iCode Systems (Replies direct to my email address will be ignored. Please reply to the group.)
From: dpb on 20 Jul 2010 08:45 Kevin Provance wrote: .... > I'm converting some C++ code to VB (specifically dealing with CAB files) and > I noticed the call was...reversed. I was just curious if there was a > specific reason why. Tis all. :-) I'd still wager the particular piece of code was written after its author had just been indoctrinated in a defensive programming training session or read the latest issue of one of the "C/C++ pitfalls" columns... :) --
From: dpb on 20 Jul 2010 09:20 dpb wrote: > Kevin Provance wrote: >> Hey C++ guys, what is the advantage or purpose of this? >> >> If (FALSE == SomeFunction()) >> { >> ... >> } >> >> Why put FALSE == instead of the function first, like we usually do? > > It's defensive coding style advocated by some--if accidently write w/ > only one "=" the non-assignable lhs will trigger compilation error. > > AFAIK that's the only purpose (but I'm no C/C++ guru, I've just seen it > as one of the suggestions in Dan Saks columns amongst other places iirc). And, of course, unless there's a specific reason to be testing specifically for the FALSE case it's silly affectation to write anything other than if( !SomeFunc() ) { ... anyway, in which case the possibility of an assignment by the "normal" order in the case of the missing symbol doesn't appear. I looked for the column but didn't find it quickly; the link to the archived Embedded Systems Programming columns was/is broken and the subsequent pages to the earlier ones after the first 10 all have the same 10 columns linked to which didn't happen to include the one in question. I have all the paper issues but not a generic index and it's long enough ago I'm thinking I'll not be leafing thru to try to find it that way any time soon... :) --
From: Jeff Johnson on 20 Jul 2010 10:08 "dpb" <none(a)non.net> wrote in message news:i22ukn$oev$1(a)news.eternal-september.org... >> Hey C++ guys, what is the advantage or purpose of this? >> >> If (FALSE == SomeFunction()) >> { >> ... >> } >> >> Why put FALSE == instead of the function first, like we usually do? > > It's defensive coding style advocated by some--if accidently write w/ only > one "=" the non-assignable lhs will trigger compilation error. > > AFAIK that's the only purpose (but I'm no C/C++ guru, I've just seen it as > one of the suggestions in Dan Saks columns amongst other places iirc). This is the explanation I've always heard, too.
From: Paul Clement on 20 Jul 2010 10:39
On Mon, 19 Jul 2010 21:28:37 -0400, "Kevin Provance" <k(a)p.c> wrote: � Hey C++ guys, what is the advantage or purpose of this? � � If (FALSE == SomeFunction()) � { � ... � } � � Why put FALSE == instead of the function first, like we usually do? Looks like the Yoda School of Programming to me. Coded properly, the comparison to FALSE isn't even necessary. Paul ~~~~ Microsoft MVP (Visual Basic) |