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in reply to Two simple code style advice questions

I like code that I can see exactly what is going on without going back and forth in the lines of code. Especially when a script becomes gargantuan. In your first case: 

my %tests = map { $_ => 0 ) qw/ tfred tjock tfortytwo / ;

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would be my preferred style. I could also go with: 
my $tests ={};
map { $tests -> { $_ } = 0 } qw/ tfred tjock tfortytwo /;

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as long as those two lines are next to each other in the code. Passing a reference to a hash to subs later on is more readable to my eyes that something like: 
callToSub(\%tests);

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but that is a personal preference.

In your second case I am a big fan of 

my $errstr = ( $case != OK ? $msg[$case] : "" );

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kinds of things. (Line right out of one of my projects). The term OK is the result of a stack of use constant OK =>0; sorts of things where I use constants to aid in my code's readability.

Peter L. Berghold -- Unix Professional
Peter -at- Berghold -dot- Net; AOL IM redcowdawg Yahoo IM: blue_cowdawg

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Re^2: Two simple code style advice questions
by BrowserUk (Patriarch) on Jan 16, 2013 at 14:43 UTC

    OK defined as 0? Yuck!

    That's as bad as defining TRUE as 0.

    It would be far clearer as:

    use constant NOERROR => 0;

my $errstr = ( $case != NOERROR ? $msg[$case] : "" );

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    Though I'd skip that conditional statement completely and embed the logic in the data:

    $msg[ 0 ] = ''; 

...

my $errstr = $msg[ $case ];

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    With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
    Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
    "Science is about questioning the status quo. Questioning authority".
    In the absence of evidence, opinion is indistinguishable from prejudice.
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          OK defined as 0? Yuck!

      It would seem to me that most Unix commands return 0 when things are "OK." So.. if you want to accuse me of showing my C programming roots, I plead guily.

      Peter L. Berghold -- Unix Professional
      Peter -at- Berghold -dot- Net; AOL IM redcowdawg Yahoo IM: blue_cowdawg
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        It would seem to me that most Unix commands return 0 when things are "OK."

        BUT, (and I'm still trying to get the developers here to overcome this), in shell programming, zero IS true (e.g. consider && and || in things like cmd1 && cmd2 or cmd1 || cmd2, and Perl is not shell.

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        It would seem to me that most Unix commands return 0 when things are "OK." So.. if you want to accuse me of showing my C programming roots, I plead guily.

        I understand the derivation, but still, the bland token OK has always suggested TRUE to me, and always will.

        Hence my suggested alternative of use constant NOERROR => 0; which seems less likely to cause confusion.

        That said, I wouldn't define a constant for 0 at all. It simply isn't necessary to compare against zero in Perl. The clearest idiom is simply:

        my $errstr = $case ? $msg[ $case ] : '';

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        But I'd still prefer setting $msg[ 0 ] == ''; and simply:

        my $errstr = $msg[ $case ];

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        With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
        Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
        "Science is about questioning the status quo. Questioning authority".
        In the absence of evidence, opinion is indistinguishable from prejudice.
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        Why even bother defining a constant ;) 
        no warnings;
if (0 == OK) { print 'Everything is ok here!'; }

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