Why do I get an error from XML::SAX::PurePerl::EncodingDetect although I did not load that module?

perl, xml

Solution

XML::SAX is used by XML::Simple. From the code:

# XML::Simple requires the services of another module that knows how to parse
# XML.  If XML::SAX is installed, the default SAX parser will be used,
# otherwise XML::Parser will be used.

A part of XML::SAX is XML::SAX::PurePerl::EncodingDetect. It sounds like you have some whitespace at the start of your XML, you may find this PerlMonks node helpful.

Problem

Below is the script I have written to change the value of one of the parameter in an XML file situated at a different location: ``` #!/usr/bin/perl -w use Cwd; use XML::Simple; use Data::Dumper; no warnings; my $before_upgrade_value = &pre_upgrade_value; print "Value before upgrade:: $before_upgrade_value \n"; &change_value ($before_upgrade_value); &change_value ("America"); my $after_upgrade_value = &pre_upgrade_value; print "Value after upgrade:: $after_upgrade_value \n"; print "Done \n"; sub pre_upgrade_value { my $xml = new XML::Simple; # read XML file my $input_xml = "/usr/tmp/country/CountryConfig.xml"; my $data = $xml->XMLin($input_xml); my $arg0 = $data->{COMMON}->{COUNTRY_LIST}->{Value}; print "Arg0 is $arg0 \n"; return $arg0; } sub change_value { my $arg0 = shift; my $arg1 = "ENGLAND"; my $arg2 = "/usr/tmp/country/CountryConfig.xml"; system("perl -pi -e 's/$arg0/$arg1/' $arg2"); } ``` But I am getting the following error: Unable to recognise encoding of this document at /usr/local/lib/perl5/site_perl/5.8.7/XML/SAX/PurePerl/EncodingDetect.pm line 100. Document requires an element [Ln: 1, Col: 0] Can you tell me the reason as I am not calling EncodingDetect.pm in my code?

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