open settings view
cmd,
In settings view we can search for packages and install them alternatively we can also install package using apm command if we have a textmate equivalent bundle
apm init --package language-r --convert https://github.com/textmate/r.tmbundle
You can now cd into language-r directory created by above command and run: apm link that will create a symbolic link from that package to your ~/.atom/packages folder.
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