wkt_representation =
    point_text_representation |
    curve_text_representation |
    surface_text_representation |
    collection_text_representation;

point_text_representation = "POINT" [ z_m ] point_text;

curve_text_representation =
    linestring_text_representation |
    circularstring_text_representation |
    compoundcurve_text_representation;

linestring_text_representation =
    "LINESTRING" [ z_m ] linestring_text_body;

circularstring_text_representation =
    "CIRCULARSTRING" [ z_m ] circularstring_text;

compoundcurve_text_representation =
    "COMPOUNDCURVE" [ z_m ] compoundcurve_text;

surface_text_representation =
    curvepolygon_text_representation;

curvepolygon_text_representation =
    "CURVEPOLYGON" [ z_m ] curvepolygon_text_body |
    polygon_text_representation |
    triangle_text_representation;

polygon_text_representation =
    "POLYGON" [ z_m ] polygon_text_body;

triangle_text_representation =
    "TRIANGLE" [ z_m ] triangle_text_body;

collection_text_representation =
    multipoint_text_representation |
    multicurve_text_representation |
    multisurface_text_representation |
    geometrycollection_text_representation;

multipoint_text_representation =
    "MULTIPOINT" [ z_m ] multipoint_text;

multicurve_text_representation =
    "MULTICURVE" [ z_m ] multicurve_text |
    multilinestring_text_representation;

multilinestring_text_representation =
    "MULTILINESTRING" [ z_m ] multilinestring_text;

multisurface_text_representation =
    "MULTISURFACE" [ z_m ] multisurface_text |
    multipolygon_text_representation |
    polyhedralsurface_text_representation |
    tin_text_representation;

multipolygon_text_representation =
    "MULTIPOLYGON" [ z_m ] multipolygon_text;

polyhedralsurface_text_representation =
    "POLYHEDRALSURFACE" [ z_m ] polyhedralsurface_text;

tin_text_representation =
    "TIN" [ z_m ] tin_text;

geometrycollection_text_representation =
    "GEOMETRYCOLLECTION" [ z_m ] geometrycollection_text;

linestring_text_body =
    linestring_text;

curvepolygon_text_body =
    curvepolygon_text;

polygon_text_body =
    polygon_text;

triangle_text_body =
    triangle_text;

point_text =
    empty_set |
    left_paren point right_paren ;

point =x y [ z ] [ m ] ;

x =number;
y =number;
z =number;
m =number;

linestring_text =
    empty_set |
    left_paren point { comma point } right_paren;

circularstring_text =
    empty_set |
    left_paren point { comma point } right_paren;

compoundcurve_text =
    empty_set |
    left_paren single_curve_text { comma single_curve_text } right_paren;

single_curve_text =
    linestring_text_body |
    circularstring_text_representation;

curve_text =
    linestring_text_body |
    circularstring_text_representation |
    compoundcurve_text_representation;

ring_text =
    linestring_text_body |
    circularstring_text_representation |
    compoundcurve_text_representation;

surface_text =
    "CURVEPOLYGON" curvepolygon_text_body |
    polygon_text_body;

curvepolygon_text =
    empty_set |
    left_paren ring_text { comma ring_text } right_paren;

polygon_text =
    empty_set |
    left_paren linestring_text { comma linestring_text } right_paren;

triangle_text =
    empty_set |
    left_paren linestring_text right_paren;

multipoint_text =
    empty_set |
    left_paren point_text { comma point_text  } right_paren;

multicurve_text =
    empty_set |
    left_paren curve_text { comma curve_text } right_paren;

multilinestring_text =
    empty_set |
    left_paren linestring_text_body { comma linestring_text_body } right_paren;

multisurface_text =
    empty_set |
    left_paren surface_text { comma surface_text } right_paren;

multipolygon_text =
    empty_set |
    left_paren polygon_text_body { comma polygon_text_body } right_paren;

polyhedralsurface_text =
    empty_set |
    left_paren polygon_text_body { comma polygon_text_body } right_paren;

tin_text =
    empty_set |
    left_paren triangle_text_body { comma triangle_text_body } right_paren;

geometrycollection_text =
    empty_set |
    left_paren wkt_representation { comma wkt_representation } right_paren;

empty_set ="EMPTY";

z_m = "ZM" | "Z" | "M";
left_paren = "(";
right_paren = ")";

comma = ",";
number = ?/[+-]?([0-9]+(\.[0-9]*)?|\.[0-9]+)([eE][+-]?[0-9]+)?/? ;