docs: add comment and example for Geometry.String;

refactor: rename var for Geometry methods

Author: utherbit

sql.go

@@ -36,7 +36,7 @@ type (
 func New[T geom.T](geom T) Geometry[T] { return Geometry[T]{geom} }
 
 // Scan impl sql.Scanner
-func (p *Geometry[T]) Scan(value interface{}) (err error) {
+func (g *Geometry[T]) Scan(value interface{}) (err error) {
 	var (
 		wkb []byte
 		ok  bool
@@ -60,7 +60,7 @@ func (p *Geometry[T]) Scan(value interface{}) (err error) {
 		return err
 	}
 
-	p.Geom, ok = geometryT.(T)
+	g.Geom, ok = geometryT.(T)
 	if !ok {
 		return ErrUnexpectedValueType
 	}
@@ -69,24 +69,24 @@ func (p *Geometry[T]) Scan(value interface{}) (err error) {
 }
 
 // Value impl driver.Valuer
-func (p Geometry[T]) Value() (driver.Value, error) {
-	if geom.T(p.Geom) == nil {
+func (g Geometry[T]) Value() (driver.Value, error) {
+	if geom.T(g.Geom) == nil {
 		return nil, nil
 	}
 
 	sb := &bytes.Buffer{}
-	if err := ewkb.Write(sb, binary.LittleEndian, p.Geom); err != nil {
+	if err := ewkb.Write(sb, binary.LittleEndian, g.Geom); err != nil {
 		return nil, err
 	}
 
 	return hex.EncodeToString(sb.Bytes()), nil
 }
 
 // GormDataType impl schema.GormDataTypeInterface
-func (p Geometry[T]) GormDataType() string {
+func (g Geometry[T]) GormDataType() string {
 	srid := strconv.Itoa(SRID)
 
-	switch any(p.Geom).(type) {
+	switch any(g.Geom).(type) {
 	case *geom.Point:
 		return "Geometry(Point, " + srid + ")"
 	case *geom.LineString:
@@ -106,10 +106,11 @@ func (p Geometry[T]) GormDataType() string {
 	}
 }
 
-func (p Geometry[T]) String() string {
-	if geomWkt, err := wkt.Marshal(p.Geom); err == nil {
+// String returns geometry formatted using WKT format
+func (g Geometry[T]) String() string {
+	if geomWkt, err := wkt.Marshal(g.Geom); err == nil {
 		return geomWkt
 	}
 
-	return fmt.Sprintf("cannot marshal geometry: %T", p.Geom)
+	return fmt.Sprintf("cannot marshal geometry: %T", g.Geom)
 }

sql_test.go

@@ -12,25 +12,20 @@ import (
 	"github.com/twpayne/go-geom/encoding/wkbcommon"
 )
 
-func ExamplePolygon_String() {
-	fmt.Println(Polygon{
-		Geom: geom.NewPolygon(geom.XY).MustSetCoords(
-			[][]geom.Coord{
-				{{42, 42}, {1, 1}, {2, 2}, {42, 42}},
-			}),
-	}.String())
-
-	// Output: POLYGON ((42 42, 1 1, 2 2, 42 42))
-}
+func ExampleGeometry_String() {
+	point := Geometry[geom.T]{
+		Geom: geom.NewPoint(geom.XY).MustSetCoords(geom.Coord{42, 42}),
+	}
 
-func ExamplePoint_String() {
-	fmt.Println(Point{
-		Geom: geom.NewPoint(geom.XY).MustSetCoords(
-			geom.Coord{42, 42},
-		).SetSRID(4326),
-	}.String())
+	polygon := Geometry[geom.T]{
+		Geom: geom.NewPolygon(geom.XY).MustSetCoords(
+			[][]geom.Coord{{{42, 42}, {1, 1}, {2, 2}, {42, 42}}}),
+	}
 
+	fmt.Println(point.String())
+	fmt.Println(polygon.String())
 	// Output: POINT (42 42)
+	// POLYGON ((42 42, 1 1, 2 2, 42 42))
 }
 
 func TestGeometryStringExpectCannotMarshal(t *testing.T) {