Avoiding "warning: Use of uninitialized value" when fetching an integer CGI parameter

Question

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;
}

• 200_success: What is the param function?
• Leo Galleguillos: 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.

Answer 1

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);

• 200_success: By the way, if you think you should interpret an erroneous "0" parameter value as page 1, then you should use the || operator instead.