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reuse

The goal of reuse is to avoid re-running slow computations, particularly in pipes.

reuse::reuse() combines features of pins::pin_read() and pins::pin_write() with some differences:

  • You can use it anywhere in a pipe.
  • You don’t have to specify the board explicitly.
  • You can update the cache inside reuse() or globally with options().

Installation

You can install the development version of reuse like so:

# install.packages("devtools")
devtools::install_github("maurolepore/reuse")

Example

  • Is plays well with the pipe.
  • It saves computations, reusing the cache if possible.
one <- 1 %>% reuse("one")
#> Creating new version '20220330T212355Z-4ebb2'
#> Writing to pin 'one'
two <- 2 %>% reuse("one")
two
#> [1] 1
  • You can update the cache for one call with the argument update.
two <- 2 %>% reuse("one", update = TRUE)
#> Replacing version '20220330T212355Z-4ebb2' with '20220330T212355Z-63a73'
#> Writing to pin 'one'
two
#> [1] 2
  • You can update the cache for one session with the option reuse.update.
options(reuse.update = TRUE)

three <- 3 %>% reuse("one")
#> Replacing version '20220330T212355Z-63a73' with '20220330T212355Z-f9a7c'
#> Writing to pin 'one'
three
#> [1] 3
  • The default cache folder uses the appropriate directory for Linux, Mac, and Windows, via the rappdirs package.
cache_dir <- rappdirs::user_cache_dir("reuse")
dir.exists(file.path(cache_dir, "one"))
#> [1] TRUE
  • It’s based on the pins package, which you can use to manage your cache folder a.k.a. “board”.
library(pins)

board <- board_folder(cache_dir)
board %>% pin_meta("one")
#> List of 11
#>  $ file       : chr "one.qs"
#>  $ file_size  : 'fs_bytes' int 46
#>  $ pin_hash   : chr "f9a7c94233173a90"
#>  $ type       : chr "qs"
#>  $ title      : chr "one: a pinned double vector"
#>  $ description: NULL
#>  $ created    : POSIXct[1:1], format: "2022-03-30 18:23:00"
#>  $ api_version: num 1
#>  $ user       : list()
#>  $ name       : chr "one"
#>  $ local      :List of 3
#>   ..$ dir    : 'fs_path' chr "~/.cache/reuse/one/20220330T212355Z-f9a7c"
#>   ..$ url    : NULL
#>   ..$ version: chr "20220330T212355Z-f9a7c"

board %>% pin_delete("one")
  • You can use a custom cache folder with the argument board.
custom <- pins::board_folder(tempdir())
1 %>% reuse("abc", board = custom)
#> Creating new version '20220330T212355Z-4ebb2'
#> Writing to pin 'abc'
#> [1] 1

pins::pin_read(board = custom, "abc")
#> [1] 1
  • You can use a custom cache folder with the option reuse.board.
options(reuse.board = custom)
1 %>% reuse("def", board = custom)
#> Creating new version '20220330T212355Z-4ebb2'
#> Writing to pin 'def'
#> [1] 1

pins::pin_exists(board = custom, "def")
#> [1] TRUE