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Everybody seems to be happy with the presence of defined-or (//) operator in Perl 5.10, including me. As I often write:
my $default = 0; my $input_number = $ARGV[0]; my $number = defined $input_number ? $input_number : $default;
Now I can write:
my $number = $input_number // $default;
Lacking of chances to download and install Perl 5.10 and test it myself (which can be read as 'lazy' :-) ), I wonder if any monks have experiences on using this one of new-long-waited-features in sequential. Take a look at this example:
my $default_theme = get_default_theme(); my $global_config = read_config('/path/to/config_file'); my $theme_config = read_config($global_config->{theme_file}); my $current_mode = get_current_mode(); my $theme = defined $global_config->{modes}{$current_mode}{theme} ? $global_config->{modes}{$current_mode}{theme} : defined $theme_config->{current_theme} ? $theme_config->{current_theme} : defined $default_theme ? $default_theme : 'none';
With defined-or operator, can I simply write
my $theme = $global_config->{modes}{$current_mode}{theme} // $theme_config->{current_theme} // $default_theme // 'none';
or, should I use some parens to delimit the (inner) expressions such as,
my $theme = ( ( $global_config->{modes}{$current_mode}{theme} // $theme_config->{current_theme} ) // $default_theme ) // 'none';
Is there any other alternative? Is this possible at all?

Thanks all for sharing your experiences.


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In reply to Sequential defined-or operators by naikonta

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