In below code I am checking if $options are defined or not, if not then i am assigning respective file name to variables but without defined it work but with defined i am getting 1 as a value for variable rather than actual value, Any suggestion?please,

my $source_file= defined($options{o}) || 'as.xcf-dist';
my $config_file= defined($options{c}) || 'config.ini';
my $dest_file= defined($options{x}) || usage();
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