Having considered the move for quite a while, this evening I finally decided to migrate from RVM to rbenv. The tipping point came as I was freeing up space on my laptop’s hard disk and discovered that the .rvm directory was occupying 21G, which seemed rather excessive.
Having jettisoned RVM, installed rbenv and ruby-build, I set about installing various versions of Ruby.
Despite the fact that Ruby 2.0.0 has recently been released and Matz has strongly encouraged users to upgrade from 1.8.7, which is due for end of life this June, I still have one customer I need to support on 1.8.7 for the time being.
This brings me to the point of this post. Unlike later versions, I struck a couple of problems with installing 1.8.7 with rbenv, just as I had done recently with RVM.
The solution was to use configuration options to tell rbenv where to get readline and to not bother with installing tcl and tk:
$ CONFIGURE_OPTS="--with-readline-dir=$(brew --prefix readline) --without-tcl --without-tk" rbenv install 1.8.7-p371