These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.01 s (backtrack: 0/20).

[ebuild  N     ] dev-perl/common-sense-3.750.0::gentoo  PERL_FEATURES="ithreads (-debug) -quadmath" 14 KiB
[ebuild  N     ] dev-perl/Canary-Stability-2013.0.0::gentoo  PERL_FEATURES="ithreads (-debug) -quadmath" 5 KiB
[ebuild  N     ] dev-perl/Types-Serialiser-1.10.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 7 KiB
[ebuild  N     ] dev-perl/JSON-XS-4.40.0::gentoo  USE="-examples -test" PERL_FEATURES="ithreads (-debug) -quadmath" 86 KiB
[ebuild  N     ] dev-perl/JSON-4.100.0::gentoo  USE="xs -examples -test" PERL_FEATURES="ithreads (-debug) -quadmath" 93 KiB
[ebuild  N     ] dev-perl/MediaWiki-API-0.520.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 32 KiB

Total: 6 packages (6 new), Size of downloads: 234 KiB