Note that it's called the conditional operator. It's merely one of a few ternary operators.

If you wanted to use the conditional operator, it would look like the following:

    $broken->{this}    = $_ eq 'this'    ? 1 : $broken->{this};
    $broken->{that}    = $_ eq 'that'    ? 1 : $broken->{that};
    $broken->{another} = $_ eq 'another' ? 1 : $broken->{another};
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But that would be silly.

You want

$broken->{$_} = 1 for @list;
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or

my @valid = qw( this that another );

$broken->{$_} = 0 for @valid;
$broken->{$_} = 1 for @list;
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or

my %valid = map { $_ => 1 } qw( this that another );

$broken->{$_} = 1 for grep $valid{$_}, @list;
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or

my @valid = qw( this that another );
my %valid = map { $_ => 1 } @valid;

$broken->{$_} = 0 for @valid;
$broken->{$_} = 1 for grep $valid{$_}, @list;
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