The CPAN software infrastructure only works for things that it was intended to do, it is very hard to make it do arbitrary things. If you want to find out what file to download from the BackPAN to get Foo::Bar 0.2, that's too bad, you have to download the BackPAN and index it yourself. Of course, there is no way to index things without evalling code regexed out of every file. (And there is no way to predict if "make install" will actually install Foo::Bar.)
Something CPAN couldn't easily do a few years ago was install to arbitrary directories. If you set the right environment variables, EUMM would sort of do the right thing. If you set different environment variables, sometimes MB would do the right thing. Eventually EUMM and MB were patched so that it almost always worked, and then local::lib was written to paper over the differences.
And of course, nothing requires the use of EUMM or MB, so if a package doesn't use it, you can't install it to your home directory.
Anyway, the EUMM is what you get when you write code to fix problems that people complain about. MB is what you get when you write specs to "fix" problems people complain about. Maybe someday we will have a build system that has a sane design and actually works.
Something CPAN couldn't easily do a few years ago was install to arbitrary directories. If you set the right environment variables, EUMM would sort of do the right thing. If you set different environment variables, sometimes MB would do the right thing. Eventually EUMM and MB were patched so that it almost always worked, and then local::lib was written to paper over the differences.
And of course, nothing requires the use of EUMM or MB, so if a package doesn't use it, you can't install it to your home directory.
Anyway, the EUMM is what you get when you write code to fix problems that people complain about. MB is what you get when you write specs to "fix" problems people complain about. Maybe someday we will have a build system that has a sane design and actually works.