moodymudskipper / loop

Alternatives to apply Functions

loop

{loop} contains two functions, loop unifies lapply and Map, loop2 unifies sapply and mapply.

Both support a dollar notation so that we can leverage the autompletion of function arguments. Arguments to be looped on are prefixed with +.

library(loop)
loop(rep)(+11:12, 2)   # rather than `lapply(11:12, rep, 2)`
#> [[1]]
#> [1] 11 11
#> 
#> [[2]]
#> [1] 12 12
loop$rep(+11:12, 2)    # same thing, but we benefit from autocomplete
#> [[1]]
#> [1] 11 11
#> 
#> [[2]]
#> [1] 12 12
loop$rep(+11:12, +1:2) # rather than `Map(rep, 11:12, 1:2)`
#> [[1]]
#> [1] 11
#> 
#> [[2]]
#> [1] 12 12

# rather than `Map(function(...) rep(..., each =2), 11:12, 1:2)` :
loop$rep(+11:12, +1:2, each = 2)
#> [[1]]
#> [1] 11 11
#> 
#> [[2]]
#> [1] 12 12 12 12

l <- list(iris, cars)
loop2$nrow(+l) # rather than `sapply(l, nrow)`
#> [1] 150  50

# we can loop on nested "plussed" arguments too
loop$mean(c(+11:12,+1:2))
#> [[1]]
#> [1] 6
#> 
#> [[2]]
#> [1] 7

Installation

Install with :

remotes::install_github("moodymudskipper/loop")

Why ?

We get used to the apply functions, but :

• They’re hard to grasp at first
• No way to leverage the applied function’s autocomplete
• The IDE highlights the apply function, not the applied function
• No need to shuffle the arguments when going from lapply to Map or sapply to mapply
• Much more compact to use constant arguments with Map and mapply
• I believe its more intuitive to have the applied function first