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up vote 2 down vote favorite

I was using this code to fetch a CGI parameter:

$page = int(param('page'));

This sometimes results in:

warning: Use of uninitialized value in int

Is this a good solution to resolve this warning, or is better and more succinct code available?

if (defined param('page')) {
    $param_page = int(param('page'));
} else {
    $param_page = 1;
}
share|improve this question
    
What is the param function? – 200_success♦ Jun 15 '16 at 20:50
    
I have use CGI qw/:standard/ at the top of my script which imports the param() function. param() gets a value from the query string. – Leo Galleguillos Jun 15 '16 at 20:53
up vote 5 down vote accepted

Standard practice is to scope variables using my.

Since Perl 5.10, the preferred way to write this is to use the logical defined-or operator to provide a default value when undef is encountered.

my $param_page = int(param('page') // 1);
share|improve this answer
    
I have not seen // before. Thank you! – Leo Galleguillos Jun 15 '16 at 21:02
2  
By the way, if you think you should interpret an erroneous "0" parameter value as page 1, then you should use the || operator instead. – 200_success♦ Jun 15 '16 at 21:05
    
Makes sense. Thank you. – Leo Galleguillos Jun 15 '16 at 21:12

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