Ruby on rails installation tricks

# On MAC OS High Sierra 10.13.6
# You must recompile Ruby with OpenSSL error:

$ rvm get head
$ rvm pkg remove
$ rvm requirements run
# (I just ran the `rvm requirements` and it installed the missing parts. 
# I then reinstalled the newest version of Ruby and  Rails, this worked for me.)
$ rvm reinstall 2.6.0

# also
$ rvm get head
$ rvm pkg remove
$ rvm remove ruby
$ rvm install ruby --debug

# and this if there are any native gems that can interfere with the process (like  apple-gcc42)
$ brew uninstall apple-gcc42
$ brew cleanup
$ softwareupdate --all
$ rvm pkg remove
$ rvm clean
$ brew install openssl
$ rvm install 2.0.0 --with-openssl-dir=`brew --prefix openssl`

# To uninstall:
$ sudo gem uninstall rails -v 4.0.0
$ sudo gem uninstall railties -v 4.0.0
# or if rails gem was installed without sudo command just run: 
$ gem uninstall rails
$ gem uninstall railities
# also can do :
$ gem uninstall -a rails
#or delete your .gem folder in the $HOME directory:
$ rm -rf ~/.gem

# if openssl is missing run:
$ rvm install openssl
# tnen remove existing ruby with
$ rvm remove 2.6.0
# than reinstall compiled ruby
$ rvm install 2.6.0 --with-openssl-dir=$HOME/.rvm/usr
# set the default Ruby version:
$ rvm use 2.6.0 --default