Update to 0.22:

0.22    2013-01-30 23:35 UTC
        + Chg : perl 5.6.1 is required.
        + Fix : context_info() now ignores %warnings::Bits for perl 5.8.6 and
                below, just like caller().
        + Fix : [RT #82220] : Scope-Upper-0.21 test stuck on Windows perl 5.12.3
                t/93-pod-spelling.t will not crash anymore on perl 5.12 and
                below.
                Thanks Gabor Szabo for reporting and Slaven Rezic for debugging
                this issue.
        + Tst : Rare test failures of t/07-context_info.t on perl 5.6,
                t/55-yield-target.t on perl 5.[68], and t/63-uplevel-ctl.t on
                perl 5.8.[345] have been addressed.

0.21    2012-09-21 15:10 UTC
        + Fix : context_info() has been taught about perl 5.17.4.
        + Fix : t/07-context_info.t will no longer fail with perls that have
                sitecustomize enabled (like many perl builds for Windows).
                Thanks Steve Hay and Nicholas Clark for debugging help.
        + Fix : Broken linkage on Windows with gcc 3.4, which appears in
                particular when using ActivePerl's default compiler suite.
                For those setups, the Scope::Upper shared library will now be
                linked against the perl dll directly (instead of the import
                library).

0.20    2012-09-17 11:00 UTC
        + Add : The new yield(@values, $context) function can be used to return
                values to any upper scope, including do or map blocks.
                The new leave(@values) function is an alias for
                yield(@values, HERE).
        + Add : The new context_info($context) function return information
                about context $context, similarly to what caller() provides
                but for any upper scope.
        + Chg : Contexts are now normalized. In previous versions, it was
                possible for different contexts to refer to the same scope :
                for example, "for (my $i = 0; $i < 10; ++$i) { ... }" was
                reachable through two contexts, while "for (@array) { ... }"
                only by one. Starting from this version, contexts are
                normalized so that they always represent an actual scope.
        + Doc : C++ compilers are officially NOT supported.
        + Fix : Building with a more recent version of perl 5.17.4.
        + Fix : Debugger compatibility with perl 5.17.1 and above.

0.19    2012-09-01 13:25 UTC
        + Doc : POD headings have been made linkable.
        + Fix : Building with perl 5.17.4.
        + Fix : BUILD_PREREQS are now set for ExtUtils::MakeMaker.
        + Opt : uplevel() private data structure is 7% smaller on 64 bits
                architectures.
        + Tst : Author tests overhaul.

(wiz)