in reply to Re: What modules should be added to the corelist?
in thread What modules should be added to the corelist?

Modules (usually XS, but some pragmata are pure Perl) that are intricately tied to the core and are effectively "optional builtins".

You mean the modules called "core extensions" in Config::Extensions? 

perl -MConfig::Extensions=%Extensions -e 'for (sort{lc$a cmp lc$b}keys
+ %Extensions){print"$_\t$Extensions{$_}\n"}'

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Why are some core modules referred to as "extensions"?

In Section Meditations