library(devtools)

#' Update all github installed packages.
#'
#' This will trash any non-master branch installs, and spend time re-installing
#' packages which are already up-to-date.
update_github <- function() {
  pkgs = loadedNamespaces()
  print(pkgs)
  desc <- lapply(pkgs, packageDescription, lib.loc = NULL)
  for (d in desc) {
    message("working on ", d$Package)
    if (!is.null(d$GithubSHA1)) {
      message("Github found")
      install_github(repo = d$GithubRepo, username = d$GithubUsername)
    }
  }
}

# test it:
# install github version of tidyr
install_github("hadley/tidyr")
library(tidyr)
update_github()

如果您安装的github安装比user/repo的master分支更复杂，请不要运行它.如果您有很多github安装，也要小心，因为这会盲目地将它们全部重新安装，即使是最新的.这可能会花费很长时间，并且如果github master分支没有处于***状态，也可能会破坏工作包.

Don't run this if you have any github installations from anything more complicated than the master branch of user/repo. Also be careful if you have a lot of github installations, since this will blindly reinstall them all, even if up-to-date. This could take a long time, and also might break working packages if github master branches are not in tip top condition.

有关详细信息，请查看devtools R/session_info.r.

Take a look at devtools R/session_info.r for details.