[cwyers]

map() in purrr is functionally equivalent to lapply(). If you can do something in lapply, you can do it with map.

[notafraudster]

Right, which is why my example used its cousin, apply, instead of lapply. apply over the row margins of a data frame does not have an equivalent in tidyverse.

[hadley]

Beware that apply() coerces data frames to matrices, which is time consuming and forces all columns to have the same type.