change default field value ?

[mdsumner]

make it polygon index, not 1 - can be set to a constant but polygon identity is surely more important than a mask ( we don't have bool type for example)

[mdsumner]

this is what the new behaviour would do (this is excellent because now the raster values is a fast lookup or pixel-group-index)

  library(sf);sf_use_s2(FALSE);sink(tempfile());example(read_sf);sink(NULL)
library(fasterize)

plot(fasterize(nc, raster(nc, res = .01)))

^{Created on 2022-12-08 with reprex v2.0.2}

this is what current behaviour does

  library(sf);sf_use_s2(FALSE);sink(tempfile());example(read_sf);sink(NULL)
library(fasterize)

plot(fasterize(nc, raster(nc, res = .01)))

^{Created on 2022-12-08 by the reprex package (v2.0.1)}