Temporarily change the here() root
Usage
with_here(new_here, expr, chdir = FALSE, verbose = FALSE)
local_here(
new_here,
chdir = FALSE,
verbose = FALSE,
.local_envir = parent.frame()
)Arguments
- new_here
new temporary here root directory
- expr
expression to evaluate
- chdir
also temporarily change working directory
- verbose
show here's messages on setting new root
- .local_envir
the environment to use for scoping, see
withr::local_dir()
Value
with_here() returns the result of the
expression. local_here() returns the original value of
here(), before the change.
Details
Changes here::here() to temporarily point to a new
directory. Automatically changes back to the original value when
finished.
The with_* and local_* flavours of this functionality mimics that which is typically used in the withr package.
Examples
library(here)
#> here() starts at /home/runner/work/wither/wither
library(withr)
d <- local_tempdir()
cat("here() is initially:", here(), "\n")
#> here() is initially: /home/runner/work/wither/wither
# temporarily do things uner a different here() root:
with_here(d, cat("but here() is now:", here(), "\n"))
#> Error in with_here(d, cat("but here() is now:", here(), "\n")): new_here must be a directory
# check that everything is shifted back
cat("here() is now again:", here(), "\n")
#> here() is now again: /home/runner/work/wither/wither
local({
d <- local_tempdir()
cat("here was initially: ", here(), "\n")
local_here(d)
cat("after local_here(), here() is: ",here(),"\n")
stopifnot(normalizePath(d) == normalizePath(here()))
# do something that requires here() be elsewhere
})
#> here was initially: /home/runner/work/wither/wither
#> here() starts at /tmp/Rtmp8rziX4/file134119a13caf
#> after local_here(), here() is: /tmp/Rtmp8rziX4/file134119a13caf
#> here() starts at /home/runner/work/wither/wither
cat("outside the block, here() is again:", here(), "\n")
#> outside the block, here() is again: /home/runner/work/wither/wither