RegionQ

RegionQ[reg] gives True if reg is a valid region and False otherwise.

Examples

Check a disk:

RegionQ[Disk[]]
(* True *)

Invalid region:

RegionQ[123]
(* False *)

Polygon:

RegionQ[Polygon[{{0, 0}, {1, 0}, {0, 1}}]]
(* True *)

Please visit the official Wolfram Language Reference for more details.