README.md

In maurolepore/reuse: Reuse R Objects

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

library(reuse)

• 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

maurolepore/reuse documentation built on May 1, 2022, 7:34 a.m.