Conflict with spatstat via units

[andybega]

Functions like st_length() that return an object with class "units" can produce a (false) error when the package "spatstat" is also attached due to a conflict between "units" and "spatstat":

library("sf")
library("units")

ex <- st_sfc(st_linestring(x = matrix(1:4, 2, 2)), crs = 4326)
# works
st_length(ex)

library("spatstat")
# does not work
st_length(ex)

The last line returns this error:

Error: $ operator is invalid for atomic vectors

This is misleading as st_length(ex) actually works correctly, it is the implicit print that fails because the wrong method is used:

str(st_length(ex))
units:::print.units(st_length(ex))

Class 'units'  atomic [1:1] 156759
  ..- attr(*, "units")=List of 2
  .. ..$ numerator  : chr "m"
  .. ..$ denominator: chr(0) 
  .. ..- attr(*, "class")= chr "symbolic_units"
156759.1 m

Not sure if this should be an issue here or at https://github.com/r-quantities/units, but it popped up when I was using sf in any case.

[edzer]

Oh, lovely. Yes, either there, or at https://github.com/spatstat/spatstat. It's in any case not an sf issue.

[edzer]

Changing the order of loading packages doesn't help; my guess is that that would have helped when spatstat would export print.units as an S3method, rather than as a symbol.

[andybega]

Thanks. I opened issues at both. I guess done as far as sf is concerned.

[edzer]

OK, thanks!