When are OSM ways considered polygons?

Ways

Via: https://wiki.openstreetmap.org/wiki/Overpass_turbo/Polygon_Features

A way is considered a Polygon if

• it forms a closed loop
• and is not tagged area=no
• and at least one of the following conditions is true:
  • there is a building=* tag and its value is not building=no
  • there is a highway=* tag and its value is not highway=no and its value is either highway=services, highway=rest_area or highway=escape
  • there is a natural=* tag and its value is not natural=no and its value is neither natural=coastline, natural=cliff, natural=ridge, natural=arete nor natural=tree_row
  • there is a landuse=* tag and its value is not landuse=no
  • there is a waterway=* tag and its value is not waterway=no and its value is either waterway=riverbank, waterway=dock, waterway=boatyard or waterway=dam
  • there is a amenity=* tag and its value is not amenity=no
  • there is a leisure=* tag and its value is not leisure=no
  • there is a barrier=* tag and its value is not barrier=no and its value is either barrier=city_wall, barrier=ditch, barrier=hedge, barrier=retaining_wall, barrier=wall or barrier=spikes
  • there is a railway=* tag and its value is not railway=no and its value is either railway=station, railway=turntable, railway=roundhouse or railway=platform
  • there is a area=* tag
  • there is a boundary=* tag and its value is not boundary=no
  • there is a man_made=* tag and its value is not man_made=no and its value is neither man_made=cutline, man_made=embankment nor man_made=pipeline
  • there is a power=* tag and its value is not power=no and its value is either power=plant, power=substation, power=generator or power=transformer
  • there is a place=* tag and its value is not place=no
  • there is a shop=* tag and its value is not shop=no
  • there is a aeroway=* tag and its value is not aeroway=no and its value is not aeroway=taxiway
  • there is a tourism=* tag and its value is not tourism=no
  • there is a historic=* tag and its value is not historic=no
  • there is a public_transport=* tag and its value is not public_transport=no
  • there is a office=* tag and its value is not office=no
  • there is a building:part=* tag and its value is not building:part=no
  • there is a ruins=* tag and its value is not ruins=no
  • there is a area:highway=* tag and its value is not area:highway=no
  • there is a craft=* tag and its value is not craft=no
  • there is a golf=* tag and its value is not golf=no

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Relations

https://wiki.openstreetmap.org/wiki/Relation:boundary