Lest provides two functions for vectorised conditional recoding of variables. case_when() enables you to vectorise multiple if and else statements (like CASE WHEN in SQL). if_else() is a stricter and more predictable version of base::ifelse() that preserves attributes (and therefore works with Dates). The functions in lest are forks of the dplyr functions of the same name.

## Why use lest?

Use this package if you like the semantics of dplyr::case_when(), but do not want to use dplyr because of the dependencies it comes with. If you already use dplyr in your project, you gain no advantage from lest. lest::case_when() and lest::if_else() behave exactly identical to the dplyr equivalents, just that they do not support tidyeval syntax (like !!!).

## Dependencies

lest depends only on base R, and will never add any external dependencies.

## Installation

You can install lest from GitHub with:

# install.packages("devtools")
devtools::install_github("s-fleck/lest")

## Example

x <- 1:50

case_when(
x %% 35 == 0 ~ "fizz buzz",
x %% 5 == 0 ~ "fizz",
x %% 7 == 0 ~ "buzz",
TRUE ~ as.character(x)
)

case_when(
x %% 35 == 0 ~ 35,
x %% 5 == 0 ~ 5,
x %% 7 == 0 ~ 7,
TRUE ~ NA
)