memoise.md

f <- function(x) Sys.sleep(x)

# takes 3 seconds always
system.time(f(3))
#>    user  system elapsed 
#>   0.000   0.000   3.003

system.time(f(3))
#>    user  system elapsed 
#>   0.017   0.003   3.021

fm <- memoise::memoise(f)

# takes 3 seconds only the first time
system.time(fm(3))
#>    user  system elapsed 
#>   0.001   0.001   3.004

# subsequent calls take virtually no time
system.time(fm(3))
#>    user  system elapsed 
#>   0.028   0.000   0.029

^{Created on 2024-06-06 with reprex v2.1.0}