{
  "name": "distance",
  "type": "function",
  "description": "Returns the minimum distance (based on spatial ref) between two geometries in projected units.",
  "arguments": [ {"arg":"geometry a","description":"a geometry"},
  {"arg":"geometry b","description":"a geometry"}],
  "examples": [ { "expression":"distance( geom_from_wkt( 'POINT(4 4)' ), geom_from_wkt( 'POINT(4 8)' ) )", "returns":"4"}
  ]
}