Print Page - Parenthesis in grund.cc

Title: Parenthesis in grund.cc
Post by: gerw on May 22, 2009, 07:19:37 PM

Is the parenthesis in line 603 wilfully placed as it is?


fence_west = (flags&has_way1)==0  ||  (static_cast<weg_t*>(obj_bei(0))->get_ribi_unmasked()&ribi_t::west)==0
	&& ( (flags&has_way2)==0  ||  (static_cast<weg_t *>(obj_bei(1))->get_ribi_unmasked()&ribi_t::west)==0);

I and my complier would prefer (since && has precedence before ||)

Code Select


fence_west = ( (flags&has_way1)==0  ||  (static_cast<weg_t*>(obj_bei(0))->get_ribi_unmasked()&ribi_t::west)==0 )
	&& ( (flags&has_way2)==0  ||  (static_cast<weg_t *>(obj_bei(1))->get_ribi_unmasked()&ribi_t::west)==0);

However, the code seems to be ok.

Title: Re: Parenthesis in grund.cc
Post by: prissi on May 24, 2009, 08:06:50 PM

Actually, if no way1 is there there will be no way2. Using short curcuit evaluation the evaluation will without extra paranthese stop after way1==0; with parentheses it will always have to check for way2, even if way1 is not there.

Title: Re: Parenthesis in grund.cc
Post by: Dwachs on May 25, 2009, 07:30:33 PM

what about this:

Code Select


fence_west = (flags&has_way1)==0  || 
             ( (static_cast<weg_t*>(obj_bei(0))->get_ribi_unmasked()&ribi_t::west)==0 &&
               ( (flags&has_way2)==0  ||  (static_cast<weg_t >(obj_bei(1))->get_ribi_unmasked()&ribi_t::west)==0) );

Title: Re: Parenthesis in grund.cc
Post by: prissi on May 25, 2009, 07:58:26 PM

Those are the intended (and need to go also on the other direction then ...

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Development => Patches & Projects => Incorporated Patches and Solved Bug Reports => Topic started by: gerw on May 22, 2009, 07:19:37 PM