As has been explained, your ERROR_SW
is a constant, and may not contain run-time variables
If you intended $switch_ip
and $timeout
to also be constant values then, because use constant
is evaluated at compile time, you would also have to declare and define these two variables beforehand. Like this
use strict;
use warnings 'all';
my ($switch_ip, $timeout);
BEGIN {
($switch_ip, $timeout) = qw/ 127.0.0.1 30 /;
}
use constant {
ERROR_SW => {
errorCode => 727,
message => "Not able to ping switch $switch_ip in $timeout seconds",
fatal => 1,
web_page => 'http://www.errorsolution.com/727',
}
};
sub error_post {
my ($error) = @_;
print( $error->{message} );
}
error_post(ERROR_SW);
However I think you meant the message to vary with the values of these variables, which is impossible with a constant. The usual way is to define an error message to have constant error message string that contain printf
field specifiers. Like this, for instance
use strict;
use warnings 'all';
use constant {
ERROR_SW => {
errorCode => 727,
message => "Not able to ping switch %s in %s seconds",
fatal => 1,
web_page => 'http://www.errorsolution.com/727',
}
};
my ( $switch_ip, $timeout ) = qw/ 127.0.0.1 30 /;
sub error_post {
my ($error) = @_;
printf $error->{message}, $switch_ip, $timeout;
}
error_post(ERROR_SW);
output
Not able to ping switch 127.0.0.1 in 30 seconds
An alternative way that choroba hinted at in his comment is to make the value of the message
field a subroutine reference. That can be executed at run time to incorporate the current values of the parameters. That solution looks like this
Note the additional parentheses at the end of $error->{message}()
to call the reference to be called instead of evaluated
use strict;
use warnings 'all';
my ($switch_ip, $timeout);
use constant {
ERROR_SW => {
errorCode => 727,
message => message => sub { "Not able to ping switch $switch_ip in $timeout seconds"},
fatal => 1,
web_page => 'http://www.errorsolution.com/727',
}
};
($switch_ip, $timeout) = qw/ 192.168.0.1 99 /;
sub error_post {
my ($error) = @_;
print( $error->{message}() );
}
error_post(ERROR_SW);
output
Not able to ping switch 192.168.0.1 in 99 seconds
3
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