> tools::package_dependencies(packages = "quantmod", which = "Depends", reverse =F)
$quantmod
[1] "xts" "zoo" "TTR" "methods"
> tools::package_dependencies(packages = "xts", which = "Depends", reverse =F)
$xts
[1] "zoo"
> tools::package_dependencies(packages = "zoo", which = "Depends", reverse =F)
$zoo
[1] "stats"
> tools::package_dependencies(packages = "stats", which = "Depends", reverse =F)