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in reply to Logical expression style

I don't like any of them (I've been trying (off and on) and failing to find a good standard for this type of thing for a long time). But I really don't like hiding the operators on the end. And I don't like adding extra parens just to "show precendence" (my eye can't match nested parens nearly as well as it can notice variations in spacing).

So now I try to line things up by precendence with the operator in front. I always put two spaces around logical expressions so I can put single spaces within them. 

    if(   defined $settings  &&  ! $setttings->{hidecode}
     and      $codtype{ $node->{nodetype} }
          or      $node->{code}
              ||  containscode( $node->{doctext} )
    #     ^1  ^2  ^3
    ) {

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So the 'arguments' to 'and' line up above "^1", the arguments to 'or' above "^2" and the arguments to '||' above "^3". I think I've finally found a standard for this that I like. (:

        - tye (but my friends call me "Tye")

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Re: (tye)Re: Logical expression style
by VSarkiss (Monsignor) on Jul 12, 2002 at 17:58 UTC

    I think I do about the same thing, but isn't this slightly misleading? Since the or binds least tightly, if I were to show precedence, I'd do:

    if (       defined $settings && ! $settings->{hidecode}
       and $codtype{ $node->{nodetype} }
    or     $node->{code}
       ||  containscode( $node->{doctext} )
) {
# ...

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    In other words, I'd line up the horns of the or at the outermost level, and then the and, etc.

    Or did I miss the point you were trying to make? (No pun intended ;-)

    This is similar to how I indent SQL where clauses:

    where
       EXISTS (select 1 from users where
               users.user_id = acct.user_id
    or    (acct_id is null
       and user_id = 0)

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      Yes, it was a contrived example and I did it wrong. ):

              - tye (but my friends call me "Tye")
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Re: (tye)Re: Logical expression style
by Sifmole (Chaplain) on Jul 12, 2002 at 17:11 UTC
    Tye,

    I think I would go cross-eyed trying to read that! Just looking at it gives me that "all over the place" feeling.

    I tend to use the operator at the end method.

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Re: (tye)Re: Logical expression style
by Anonymous Monk on Jul 12, 2002 at 17:52 UTC
    Omigod! My eyes! I looked directly at the code! 
    if (
    ( defined $settings && ! $settings->{hidecode} )     &&
    ( $codetype{ $node->{nodetype} } )                   ||
    ( $node->{code} || containscode( $node->{doctext} ) )
   ) {

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    A few extra parens makes it much more readable in my opinion.

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