Error in map_size: could not find function "lengths"

[hayneswa]

The function "lengths" was first introduced in R version 3.2.0 and is called by map_size (and several other functions). Running with an earlier version of R results in the error message:
Error in map_size: could not find function "lengths"

One possible resolution is to make the dependency in the DESCRIPTION file R (>= 3.2.0).

[hayneswa]

Replacing lengths() with lapply(X, length) was able to resolve this issue for me on R 3.1.2

The changes can be seen here:
hayneswa@eb1c0a8

[cpsievert]

Thanks!