On 2/20/2012 12:31 PM, Alan W. Irwin wrote:
> Hi Arjen:
>
> I changed the subject line to something more appropriate.
>
> On 2012-02-20 10:23+0100 Arjen Markus wrote:
>
>> Hi Alan,
>>
>> I too come from a school where all declarations are put at the top
>> of a program unit, but it seems more and more "fashionable" to restrict
>> the scope of variables as much as possible, in this case the variables
>> s and p. The code in csa.c is full of that type of local declarations.
>
> Actually, I generally like that fashion/style. If you declare the
> variables at the top of the smallest block of code (delimited by "{"
> and "}") where they are used (as opposed to declaring them at the top
> of the largest possible block of code, i.e., the function where they
> are used) I just think it makes the code a lot easier to read and helps
> you to keep better track of communication of data between blocks
> of code.
>
> As stated previously in this thread, I was a bit concerned from the
> efficiency perspective with the case of declarations in a block of
> code for a loop, but I am also pretty sure your friend is right (that
> compilers will do the right thing from the efficiency perspective and
> move the stack allocations/deallocations associated with the
> declaration outside the loop).
>
> Is there anyone else here with thoughts or experience with this
> largely stylistic issue?I think current compilers can keep this efficient and lift out the initializations oft of loops and other such optimizations. A related point is that not all compilers can deal with declarations that are not at the beginning of the enclosing block (some versions of MSVC come to mind) and will complain or quit if "sloppy" C++ style declarations are used. --Chris > Alan > __________________________ > Alan W. Irwin > > Astronomical research affiliation with Department of Physics and Astronomy, > University of Victoria (astrowww.phys.uvic.ca). > > Programming affiliations with the FreeEOS equation-of-state > implementation for stellar interiors (freeeos.sf.net); the Time > Ephemerides project (timeephem.sf.net); PLplot scientific plotting > software package (plplot.sf.net); the libLASi project > (unifont.org/lasi); the Loads of Linux Links project (loll.sf.net); > and the Linux Brochure Project (lbproject.sf.net). > __________________________ > > Linux-powered Science > __________________________ > > ------------------------------------------------------------------------------ > Try before you buy = See our experts in action! > The most comprehensive online learning library for Microsoft developers > is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, > Metro Style Apps, more. Free future releases when you subscribe now! > http://p.sf.net/sfu/learndevnow-dev2 > _______________________________________________ > Plplot-devel mailing list > Plplot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/plplot-devel > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > Version: 10.0.1424 / Virus Database: 2112/4821 - Release Date: 02/20/12 > > ------------------------------------------------------------------------------ Try before you buy = See our experts in action! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-dev2 _______________________________________________ Plplot-devel mailing list Plplot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/plplot-devel
