withr: Run Code 'With' Temporarily Modified Global State
- CRAN: http://cran.r-project.org/web/packages/withr/index.html
- GitHub: http://github.com/jimhester/withr
> library(withr)
バージョン: 1.0.0
| 関数名 | 概略 |
|---|---|
with_collate |
Collation Order |
with_dir |
Working directory |
with_envvar |
Environment variables |
with_libpaths |
Library paths |
with_locale |
Locale settings |
with_makevars |
Makevars variables |
with_options |
Options |
with_par |
Graphics parameters |
with_path |
PATH environment variable |
with_temp_libpaths |
Library paths |
withr |
Execute code in temporarily altered environment |
with_dir
> dir.create("test")
> getwd()
[1] "/Users/uri/git/rpkg_showcase/development"
> with_dir("test2", getwd())
Error in setwd(dir = new): cannot change working directory
> getwd()
[1] "/Users/uri/git/rpkg_showcase/development"
> unlink("test")
with_envvar
一時的な環境変数の設定
> Sys.getenv("HADLEY")
[1] ""
> with_envvar(c("HADLEY" = "Hadley"), Sys.getenv("HADLEY"))
[1] "Hadley"
> Sys.getenv("HADLEY")
[1] ""