Package names are just strings, so I would approach the problem as follows:

use vars qw($csv_class);
if( $i_want_to_use_XS ) { 
    require Text::CSV_XS;
    $csv_class= 'Text::CSV_XS';
} else {
    require Text::CSV;
    $csv_class= 'Text::CSV';
};

my $csv= $csv_class->new(...);

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In reply to Re: Switching Modules as Necessary by Corion
in thread Switching Modules as Necessary by Melly

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