I see that we now have is_list(), is_num(), is_bool(), and is_string(), but
there is no is_range. It seems like maybe right now you can write
function is_range(x) = !is_list(x) && !is_num(x) && !is_bool(x) &&
!is_string(x), but I'm not sure if I've missed anything, and this seems kind
of clumsy. Also it's problematic down the road if a new type is ever added.
In issue 1584, I was proposing that range values should behave exactly like lists of numbers, so that is_list([1:3]) would be true. I proposed this for OpenSCAD2 and implemented it in Curv. If there are no plans to ever unify lists and ranges in OpenSCAD, then it would make sense to introduce an is_range function.
On Sat, Mar 16, 2019, at 11:23 AM, Torsten Paul wrote: