[bbox:{{bbox}}];

// get all platforms
nwr[public_transport=platform]->.platforms;
// get all stop_areas
rel[public_transport=stop_area]->.stop_areas;
// get all stop_area members
nwr(r.stop_areas)->.stop_area_members;
// all platforms not part of a stop_area
(.platforms; - .stop_area_members;)->.remaining_platforms;

// for each stop area
foreach.stop_areas {
  // recurse relation fully down (select all ancestors)
  // required to construct the full geometry for relations that contain other relations
  >>;
  // convert all stop_areas to custom zone element
  make zone
    name=min(t["name"]),
    // group geometries into one
    ::geom=gcat(geom());
  out bb;
}

// return all bboxes of stop aras and platforms not part of stop areas
// loop over every single platform element
foreach.remaining_platforms {
  // make intersection of current platform (default set ._) and .remaining_platforms
  // therefore only if the current platform is in remaining_platforms count will be 1
  // otherwise it has already been merged and therefore removed from remaining_platforms
  nwr._.remaining_platforms;
  if (count(nwr) > 0) {
    // get any nearby platforms
    // this loops for every newly found platform untill no new platforms are found
    // 10 is the max number of iterations
    complete(10) -> .grouped {
      nwr.remaining_platforms(around:75);
    }
    // delete .grouped platforms from .remaining_platfroms set
    (.remaining_platforms; - .grouped;) -> .remaining_platforms;
    // write to default set because make always reads from default set
    .grouped -> ._;
    // build the target areas
    make zone 
      name=min(t["name"]),
    // uncomment the following line to get the source remaining_platforms
    // source=set("{"+type()+" "+id()+"}"),
    // group geometries into one
    ::geom=gcat(geom());
    // output bbox only
    out bb;
  }
}

[bbox:{{bbox}}];

// get all platforms
nwr[public_transport=platform]->.platforms;
// get all stop_areas
rel[public_transport=stop_area]->.stop_areas;
// get all stop_area members
nwr(r.stop_areas)->.stop_area_members;
// all platforms not part of a stop_area
(.platforms; - .stop_area_members;)->.remaining_platforms;

(.stop_areas; .remaining_platforms;)->.remaining_platforms;

// return all bboxes of stop aras and platforms not part of stop areas
// loop over every single platform element
foreach.remaining_platforms {
  // make intersection of current platform (default set ._) and .remaining_platforms
  // therefore only if the current platform is in remaining_platforms count will be 1
  // otherwise it has already been merged and therefore removed from remaining_platforms
  nwr._.remaining_platforms;
  if (count(nwr) > 0) {
    // get any nearby platforms
    // this loops for every newly found platform untill no new platforms are found
    // 20 is the max number of iterations
    complete(20) -> .grouped {
      nwr.remaining_platforms(around:100);
    }
    // delete .grouped platforms from .remaining_platfroms set
    (.remaining_platforms; - .grouped;) -> .remaining_platforms;
    // recurse relation fully down (select all ancestors)
    // required to construct the full geometry for relations that contain other relations
    // write to default set because make always reads from default set
    (.grouped; .grouped >>;);
    // build the target areas
    make zone
      name=min(t["name"]),
    // uncomment the following line to get the source remaining_platforms
    // source=set("{"+type()+" "+id()+"}"),
    // group geometries into one
    ::geom=gcat(geom());
    // output bbox only
    out bb;
  }
}