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Re: Coding Style Question - Is there any sane reason for doing this?

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On 10.01.2012 02:11, BCFD36 wrote:
> I am working on a piece of legacy code that has many, shall we say,
> strange things. This one, as J.K. Anderson (classics Prof at UC
> Berkeley) used to say, "baffles me". It has the following statement in
> the code:
>
> const unsigned int WAKEUP_MASK = (1<<  1) ;
>
> Is there any reason for doing this,  other than to make the code even
> more obscure?

No, there is no good reason: one should in general reserve ALL UPPERCASE 
identifiers for macros.

But they should be used for macros.

Also, there is no reason for the keyword `int`.

So that's also quite baffling: is the author, like, a compulsive typist 
who just wants to type as much as possible, regardless of lack of meaning?

Anyway, the almost OK part of that code, `1 << 1`, explicitly tells you 
that this is a single bit bitmask, and which bit is set; in the context 
of the rest it's bafflingly clear & communicative. It's generally good 
to be explicit in code, and let the compiler handle the translation to 
machine code, rather than doing it oneself and writing e.g. 0x0002. The 
latter is just a number which the reader then must decompile. However, 
for the general case `1 << n` runs the risk of Undefined Behavior, since 
it is a signed expression. It should be `1u << n`.


Cheers & hth.,

- Alf

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Coding Style Question - Is there any sane reason for doing this? BCFD36 <bcfd36@aol.com> - 2012-01-09 17:11 -0800
  Re: Coding Style Question - Is there any sane reason for doing this? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2012-01-10 02:23 +0100
    Re: Coding Style Question - Is there any sane reason for doing this? legalize+jeeves@mail.xmission.com (Richard) - 2012-01-10 06:05 +0000
      Re: Coding Style Question - Is there any sane reason for doing this? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2012-01-10 07:12 +0100
        Re: Coding Style Question - Is there any sane reason for doing this? BCFD36 <bcfd36@cruzio.com> - 2012-01-09 22:35 -0800
      Re: Coding Style Question - Is there any sane reason for doing this? Gareth Owen <gwowen@gmail.com> - 2012-01-10 06:58 +0000
    Re: Coding Style Question - Is there any sane reason for doing this? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-01-10 21:58 +0000
      Re: Coding Style Question - Is there any sane reason for doing this? David Dyer-Bennet <dd-b@dd-b.net> - 2012-01-10 16:46 -0600
      Re: Coding Style Question - Is there any sane reason for doing this? jt@toerring.de (Jens Thoms Toerring) - 2012-01-10 23:41 +0000
        Re: Coding Style Question - Is there any sane reason for doing this? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-01-11 00:19 +0000
          Re: Coding Style Question - Is there any sane reason for doing this? "MikeWhy" <boat042-nospam@yahoo.com> - 2012-01-10 21:53 -0600
      Re: Coding Style Question - Is there any sane reason for doing this? Juha Nieminen <nospam@thanks.invalid> - 2012-01-11 15:14 +0000
        Re: Coding Style Question - Is there any sane reason for doing this? Victor Bazarov <v.bazarov@comcast.invalid> - 2012-01-11 11:46 -0500
  Re: Coding Style Question - Is there any sane reason for doing this? Ian Collins <ian-news@hotmail.com> - 2012-01-10 14:30 +1300
    Re: Coding Style Question - Is there any sane reason for doing this? BCFD36 <bcfd36@cruzio.com> - 2012-01-09 21:32 -0800
      Re: Coding Style Question - Is there any sane reason for doing this? Paavo Helde <myfirstname@osa.pri.ee> - 2012-01-10 01:01 -0600
        Re: Coding Style Question - Is there any sane reason for doing this? BCFD36 <bcfd36@cruzio.com> - 2012-01-09 23:11 -0800
          Re: Coding Style Question - Is there any sane reason for doing this? yatremblay@bel1lin202.(none) (Yannick Tremblay) - 2012-01-11 10:23 +0000
            Re: Coding Style Question - Is there any sane reason for doing this? yatremblay@bel1lin202.(none) (Yannick Tremblay) - 2012-01-11 10:37 +0000
        Re: Coding Style Question - Is there any sane reason for doing this? Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-10 00:30 -0800
          Re: Coding Style Question - Is there any sane reason for doing this? "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com> - 2012-01-10 16:31 +0100
            Re: Coding Style Question - Is there any sane reason for doing this? scott@slp53.sl.home (Scott Lurndal) - 2012-01-10 17:14 +0000
              Re: Coding Style Question - Is there any sane reason for doing this? Victor Bazarov <v.bazarov@comcast.invalid> - 2012-01-10 15:11 -0500
                Re: Coding Style Question - Is there any sane reason for doing this? Richard <rgrdev_@gmail.com> - 2012-01-10 21:45 +0100
                Re: Coding Style Question - Is there any sane reason for doing this? hanukas <jukka@liimatta.org> - 2012-01-11 00:04 -0800
                Re: Coding Style Question - Is there any sane reason for doing this? hanukas <jukka@liimatta.org> - 2012-01-11 00:15 -0800
                Re: Coding Style Question - Is there any sane reason for doing this? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2012-01-10 21:51 +0000
                Re: Coding Style Question - Is there any sane reason for doing this? "Bill Davy" <Bill@SynectixLtd.com> - 2012-01-11 08:30 +0000
                Re: Coding Style Question - Is there any sane reason for doing this? "Fred Zwarts \(KVI\)" <F.Zwarts@KVI.nl> - 2012-01-11 09:40 +0100
                Re: Coding Style Question - Is there any sane reason for doing this? hanukas <jukka@liimatta.org> - 2012-01-11 06:50 -0800
                Re: Coding Style Question - Is there any sane reason for doing this? scott@slp53.sl.home (Scott Lurndal) - 2012-01-11 17:28 +0000
                Re: Coding Style Question - Is there any sane reason for doing this? David Dyer-Bennet <dd-b@dd-b.net> - 2012-01-11 13:28 -0600
            Re: Coding Style Question - Is there any sane reason for doing this? jgk@panix.com (Joe keane) - 2012-01-11 17:51 +0000
            Re: Coding Style Question - Is there any sane reason for doing this? Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-01-12 05:40 -0800
              Re: Coding Style Question - Is there any sane reason for doing this? BCFD36 <bcfd36@cruzio.com> - 2012-01-12 20:42 -0800
          Re: Coding Style Question - Is there any sane reason for doing this? hanukas <jukka@liimatta.org> - 2012-01-10 23:50 -0800

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