{
  "name": "perimeter",
  "type": "function",
  "description": "Returns the perimeter of a geometry polygon object. Calculations are in the Spatial Reference System of this geometry.",
  "arguments": [ {"arg":"geometry","description":"polygon geometry object"}],
  "examples": [ { "expression":"perimeter(geom_from_wkt('POLYGON((0 0, 4 0, 4 2, 0 2, 0 0))'))", "returns":"12.0"}]
}