$ perl -Mlib=. -MMod -e'Mod::foo();'
Insufficient arguments at Mod.pm line 5.         # carp
Insufficient arguments at -e line 1.             # warn

##</code><code>##

$ PERL5OPT=-MCarp::Always perl -Mlib=. -MMod -e'Mod::foo();'
Insufficient arguments at Mod.pm line 5.
        Mod::foo() called at -e line 1
Insufficient arguments at Mod.pm line 6.
        Mod::foo() called at Mod.pm line 6.
        Mod::foo() called at -e line 1