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Perl Style: Don't Overdo `?:'

  • Using ?: for control flow may get you talked about. Better to use an if/else. And seldom if ever nest ?:.

        # BAD
        ($pid = fork) ? waitpid($pid, 0) : exec @ARGS;
    
        # GOOD:
        if ($pid = fork) {
            waitpid($pid, 0);
        } else {
            die "can't fork: $!"    unless defined $pid;
            exec @ARGS;
            die "can't exec @ARGS: $!";
        }
    
  • Best as an expression:

        $State = (param() != 0) ? "Review" : "Initial";
    
        printf "%-25s %s\n", $Date{$url}
                ? (scalar localtime $Date{$url})
                : "<NONE SPECIFIED>",
    

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Copyright © 1998, Tom Christiansen All rights reserved.

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