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A comment on Ifs and &&s and Plan 9's Source Code.

Re:Ifs and &&s and Plan 9's Source Code by triztian on Friday May 24, 2013 @03:35PM (#5764826)
How about using this alternative form:

  if((b != nil)
  &&(b->qid.type==a->qid.type)
  &&(b->qid.path==a->qid.path)
  &&(b->qid.vers==a->qid.vers)
  &&(b->dev==a->dev)
  &&(b->type==a->type)){
      fprint(2, "cp: %s and %s are the same file\n", an, bn);
      ret = 1;
    }
It keeps almost the same visual look and it uses the common convetion, except for the && at the beginning of each line.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by phoboslab on Friday May 24, 2013 @04:08PM (#5764942)
I still prefer this:

  if(
  	b != nil &&
  	b->qid.type == a->qid.type &&
  	b->qid.path == a->qid.path &&
  	b->qid.vers == a->qid.vers &&
  	b->dev == a->dev &&
  	b->type == a->type
  ) {
  	fprint(2, "cp: %s and %s are the same file\n", an, bn);
  	ret = 1;
  }
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by IvyMike on Friday May 24, 2013 @04:33PM (#5765057)
We can go deeper...

  if(
  	b != nil &&
  	b->qid.type == a->qid.type &&
  	b->qid.path == a->qid.path &&
  	b->qid.vers == a->qid.vers &&
  	b->dev      == a->dev &&
  	b->type     == a->type
  ) {
  	fprint(2, "cp: %s and %s are the same file\n", an, bn);
  	ret = 1;
  }
(Lined up the "a"s to make it obvious that they're all the same.)
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by MaulingMonkey on Friday May 24, 2013 @07:04PM (#5765710)
I'd prefer some variation on:

    int samedirfile( Dir *a, Dir *b )
    {
            if( a == b )
                    return 1;
    
            return  ( a && b ) &&
                    ( a->qid.type == b->qid.type ) &&
                    ( a->qid.path == b->qid.path ) &&
                    ( a->qid.vers == b->qid.vers ) &&
                    ( a->dev      == b->dev ) &&
                    ( a->type     == b->type );
    }
    
    ...
    
    if( samedirfile( a, b ) ) {
            fprint(2, "cp: %s and %s are the same file\n", an, bn);
            ret = 1;
    }
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by tricolon on Saturday May 25, 2013 @01:31AM (#5766476)
I think it's fascinating that we prefer styles that are almost opposites:

    int samedirfile(Dir *a, Dir *b) {
        if(a == b) {
            return 1;
        }

        return (a && b)
            && (a->qid.type == b->qid.type)
            && (a->qid.path == b->qid.path)
            && (a->qid.vers == b->qid.vers)
            && (a->dev == b->dev)
            && (a->type == b->type);
    }
    
    ...
    
    if(samedirfile(a, b)) {
        fprint(2, "cp: %s and %s are the same file\n", an, bn);
        ret = 1;
    }
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by MaulingMonkey on Tuesday May 28, 2013 @01:24AM (#5778242)
I'll note I actually have a slight preference for prepended continuation operators like you have, but I stick to the style used at work for the sake of my sanity in trying to write consistent code.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by drivebyacct2 on Saturday May 25, 2013 @07:44AM (#5766965)
I'm so, so, so glad that new languages are banning braceless if/else bodies.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by MaulingMonkey on Tuesday May 28, 2013 @01:24AM (#5778243)
So how about that python? </trololololo>
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by drivebyacct2 on Thursday May 30, 2013 @05:12AM (#5791572)
I should have of course said "some" :)
[ Parent | on HN ]
[deleted]
Re:Ifs and &&s and Plan 9's Source Code by MindTwister on Friday May 24, 2013 @05:25PM (#5765271)
I'm not sure if you're trolling or not... but isn't that the point of the function in the first place...?
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by sbmassey on Friday May 24, 2013 @08:52PM (#5765972)
Putting the &&'s at the beginning of each line makes the overall shape of the logic expression easier to percieve: you can prove they're all one big 'and' expression without having to hunt for the end of each line.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by Avshalom on Friday May 24, 2013 @05:48PM (#5765355) 

  if(b != nil){
  if(b->qid.type==a->qid.type){
  if(b->qid.path==a->qid.path){
  if(b->qid.vers==a->qid.vers){
  if(b->dev==a->dev){
  if(b->type==a->type){
    fprint(2, "cp: %s and %s are the same file\n", an, bn);
    ret = 1;
  }}}}}}
I will never understand the allergy to multiple braces on one line.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by notaddicted on Friday May 24, 2013 @06:18PM (#5765494)
I think the aversion is because the way that they line up visually is the opposite of the way that they are matched by the parser. I think everyone needs a dose of LISP to get over any problems they have with any frequency or arrangement of brackets/parens/braces. Anyway, having a function that compares two structs and returns 0 or 1 with a printf out to stderr is just gross in my opinion.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by chj on Friday May 24, 2013 @09:29PM (#5766045)
Using ifs is definitely more readable than &&, words always win. However carefully alignment of && and ( can make things better. Note that the comment after "if" is necessary to keep the shape balanced.

    if( /* b is same as a */
           (b != nil)
        && (b->qid.type == a->qid.type)
        && (b->qid.path == a->qid.path)
        && (b->qid.vers == a->qid.vers)
        && (b->dev == a->dev)
        && (b->type == a->type)
    ){
        fprint(2, "cp: %s and %s are the same file\n", an, bn);
        ret = 1;
    }
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by dllthomas on Saturday May 25, 2013 @10:33AM (#5767372)
"words always win"

Add seven to three then multiply the whole thing by twelve.

(7 + 3) * 12

[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by dave809 on Saturday May 25, 2013 @04:04PM (#5768633)
(mult (add seven three) twelve)
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by dllthomas on Saturday May 25, 2013 @04:24PM (#5768692)
Better, obviously, but I think the regular math notation still wins. It's more concise, and equally (if not more) familiar.
[ Parent | on HN ]
Re:Ifs and &&s and Plan 9's Source Code by moron4hire on Saturday May 25, 2013 @03:00PM (#5768368)
only if you treat symbols as a foreign language
[ Parent | on HN ]