This resolves #3376. I thought about adding more commands, for example to automatically write the output into a file, but I think, only the command I added is generally desirable. You can view, comment on, or merge this pull request online at:
https://github.com/geany/geany/pull/3607
-- Commit Summary --
* add R execution command
-- File Changes --
M data/filedefs/filetypes.r (5)
-- Patch Links --
https://github.com/geany/geany/pull/3607.patch https://github.com/geany/geany/pull/3607.diff