Usually the check condition if a module is present is done in BEGIN block using eval to test a require instead of use because the latter is done at compiletime.

Something like the following can be used:

my $gzip;
BEGIN{
  $gzip = eval
  {
    require IO::Compress::Gzip;
    IO::Compress::Gzip->import();
    1;                            #UPDATE as per Eily's comment: this 
+is needed 
  };
  print "IO::Compress::Gzip found!" if $gzip; 
}
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Notice also that on CPAN there is Module::Load::Conditional that can be usefull... but must be installed!

Also interesting is perlancar article

L*