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

Calculating dependencies ... done!
Dependency resolution took 0.90 s (backtrack: 1/20).


!!! All ebuilds that could satisfy ">=dev-perl/PDL-2.7.0" have been masked.
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- dev-perl/PDL-2.100.0-r1::gentoo (masked by: || ( ) PerlDL license(s))
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- dev-perl/PDL-2.93.0-r2::gentoo (masked by: || ( ) PerlDL license(s))
- dev-perl/PDL-2.63.0-r2::gentoo (masked by: || ( ) PerlDL license(s))

(dependency required by "dev-perl/Lab-Measurement-3.931::gentoo" [ebuild])
(dependency required by "=dev-perl/Lab-Measurement-3.931" [argument])
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