No. 1 indicates it loaded successfully, otherwise it failed to load successfully. use/require die when it fails to load successfully, but its still loaded.

D:\>echo package asdf; $VERSION = 5; 1; >asdf.pm

D:\>perl -Masdf -e 1

D:\>echo package asdf; $VERSION = 5; 0; >asdf.pm

D:\>perl -Masdf -e 1
asdf.pm did not return a true value.
BEGIN failed--compilation aborted.

D:\>perl -e " eval { require asdf; 1 } or warn $@; die $asdf::VERSION 
+"
asdf.pm did not return a true value at -e line 1.
5 at -e line 1.
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