{
  "name": "combine",
  "type": "function",
  "groups": ["GeometryGroup"],
  "description": "Returns the combination of two geometries.",
  "arguments": [{
    "arg": "geometry1",
    "description": "a geometry"
  }, {
    "arg": "geometry2",
    "description": "a geometry"
  }],
  "examples": [{
    "expression": "geom_to_wkt( combine( geom_from_wkt( 'LINESTRING(3 3, 4 4, 5 5)' ), geom_from_wkt( 'LINESTRING(3 3, 4 4, 2 1)' ) ) )",
    "returns": "'MULTILINESTRING((4 4, 2 1), (3 3, 4 4), (4 4, 5 5))'"
  }, {
    "expression": "geom_to_wkt( combine( geom_from_wkt( 'LINESTRING(3 3, 4 4)' ), geom_from_wkt( 'LINESTRING(3 3, 6 6, 2 1)' ) ) )",
    "returns": "'LINESTRING(3 3, 4 4, 6 6, 2 1)'"
  }],
  "tags": ["combination", "union"]
}