Suppose you have a cpanfile with:
requires 'DBI', '1.600';
requires 'Plack', '== 1.0011';
and then run "carton install" to get DBI 1.610 (the latest at that time) and Plack 1.0011 (as specified
in the requirement).
A few weeks later, DBI and Plack have been updated a couple of times. Running "carton install" won't
update the versions, because the installed versions satisfy the requirements in "cpanfile".
Running "carton update" will update DBI to the latest version, say 1.611, because the version still
satisfies the requirement. However, it won't update Plack's version, since whatever latest version on
CPAN will not satisfy the Plack's requirement "== 1.0011" because it wants an exact version.
perl v5.34.0 2022-05-12 Carton::Doc::Update(3pm)