Tie::ShadowHash 2.01

Tie::ShadowHash is a small Perl module that allows one to stack an in-memory modifiable hash on top of a read-only hash obtained from anywhere you can get a hash in Perl (including a tied hash), functioning much like an overlay file system with the same benefits.

This release just (hopefully) fixes a few test suite failures, and is probably not worth announcing except that it bugs me to not announce each software release.