Return Option<Self> in fallible constructors (#141)

Author: kylebarron

src/types/geometrycollection.rs

@@ -14,7 +14,6 @@
 
 use geo_traits::GeometryCollectionTrait;
 
-use crate::error::Error;
 use crate::to_wkt::write_geometry_collection;
 use crate::tokenizer::{PeekableTokens, Token};
 use crate::types::Dimension;
@@ -51,13 +50,13 @@ impl<T: WktNum> GeometryCollection<T> {
     ///
     /// To handle empty input iterators, consider calling `unwrap_or` on the result and defaulting
     /// to an [empty][Self::empty] geometry with specified dimension.
-    pub fn from_geometries(geoms: impl IntoIterator<Item = Wkt<T>>) -> Result<Self, Error> {
+    pub fn from_geometries(geoms: impl IntoIterator<Item = Wkt<T>>) -> Option<Self> {
         let geoms = geoms.into_iter().collect::<Vec<_>>();
         if geoms.is_empty() {
-            Err(Error::UnknownDimension)
+            None
         } else {
             let dim = geoms[0].dimension();
-            Ok(Self::new(geoms, dim))
+            Some(Self::new(geoms, dim))
         }
     }
 

src/types/linestring.rs

@@ -14,7 +14,6 @@
 
 use geo_traits::LineStringTrait;
 
-use crate::error::Error;
 use crate::to_wkt::write_linestring;
 use crate::tokenizer::PeekableTokens;
 use crate::types::coord::Coord;
@@ -46,19 +45,17 @@ impl<T: WktNum> LineString<T> {
     /// This will infer the dimension from the first coordinate, and will not validate that all
     /// coordinates have the same dimension.
     ///
-    /// ## Errors
-    ///
-    /// If the input iterator is empty.
+    /// Returns `None` if the input iterator is empty.
     ///
     /// To handle empty input iterators, consider calling `unwrap_or` on the result and defaulting
     /// to an [empty][Self::empty] geometry with specified dimension.
-    pub fn from_coords(coords: impl IntoIterator<Item = Coord<T>>) -> Result<Self, Error> {
+    pub fn from_coords(coords: impl IntoIterator<Item = Coord<T>>) -> Option<Self> {
         let coords = coords.into_iter().collect::<Vec<_>>();
         if coords.is_empty() {
-            Err(Error::UnknownDimension)
+            None
         } else {
             let dim = coords[0].dimension();
-            Ok(Self::new(coords, dim))
+            Some(Self::new(coords, dim))
         }
     }
 

src/types/multilinestring.rs

@@ -14,7 +14,6 @@
 
 use geo_traits::MultiLineStringTrait;
 
-use crate::error::Error;
 use crate::to_wkt::write_multi_linestring;
 use crate::tokenizer::PeekableTokens;
 use crate::types::linestring::LineString;
@@ -46,21 +45,19 @@ impl<T: WktNum> MultiLineString<T> {
     /// This will infer the dimension from the first line string, and will not validate that all
     /// line strings have the same dimension.
     ///
-    /// ## Errors
-    ///
-    /// If the input iterator is empty.
+    /// Returns `None` if the input iterator is empty.
     ///
     /// To handle empty input iterators, consider calling `unwrap_or` on the result and defaulting
     /// to an [empty][Self::empty] geometry with specified dimension.
     pub fn from_line_strings(
         line_strings: impl IntoIterator<Item = LineString<T>>,
-    ) -> Result<Self, Error> {
+    ) -> Option<Self> {
         let line_strings = line_strings.into_iter().collect::<Vec<_>>();
         if line_strings.is_empty() {
-            Err(Error::UnknownDimension)
+            None
         } else {
             let dim = line_strings[0].dimension();
-            Ok(Self::new(line_strings, dim))
+            Some(Self::new(line_strings, dim))
         }
     }
 

src/types/multipoint.rs

@@ -14,7 +14,6 @@
 
 use geo_traits::MultiPointTrait;
 
-use crate::error::Error;
 use crate::to_wkt::write_multi_point;
 use crate::tokenizer::PeekableTokens;
 use crate::types::point::Point;
@@ -46,19 +45,17 @@ impl<T: WktNum> MultiPoint<T> {
     /// This will infer the dimension from the first point, and will not validate that all
     /// points have the same dimension.
     ///
-    /// ## Errors
-    ///
-    /// If the input iterator is empty.
+    /// Returns `None` if the input iterator is empty.
     ///
     /// To handle empty input iterators, consider calling `unwrap_or` on the result and defaulting
     /// to an [empty][Self::empty] geometry with specified dimension.
-    pub fn from_points(points: impl IntoIterator<Item = Point<T>>) -> Result<Self, Error> {
+    pub fn from_points(points: impl IntoIterator<Item = Point<T>>) -> Option<Self> {
         let points = points.into_iter().collect::<Vec<_>>();
         if points.is_empty() {
-            Err(Error::UnknownDimension)
+            None
         } else {
             let dim = points[0].dimension();
-            Ok(Self::new(points, dim))
+            Some(Self::new(points, dim))
         }
     }
 

src/types/multipolygon.rs

@@ -14,7 +14,6 @@
 
 use geo_traits::MultiPolygonTrait;
 
-use crate::error::Error;
 use crate::to_wkt::write_multi_polygon;
 use crate::tokenizer::PeekableTokens;
 use crate::types::polygon::Polygon;
@@ -46,19 +45,17 @@ impl<T: WktNum> MultiPolygon<T> {
     /// This will infer the dimension from the first polygon, and will not validate that all
     /// polygons have the same dimension.
     ///
-    /// ## Errors
-    ///
-    /// If the input iterator is empty.
+    /// Returns `None` if the input iterator is empty.
     ///
     /// To handle empty input iterators, consider calling `unwrap_or` on the result and defaulting
     /// to an [empty][Self::empty] geometry with specified dimension.
-    pub fn from_polygons(polygons: impl IntoIterator<Item = Polygon<T>>) -> Result<Self, Error> {
+    pub fn from_polygons(polygons: impl IntoIterator<Item = Polygon<T>>) -> Option<Self> {
         let polygons = polygons.into_iter().collect::<Vec<_>>();
         if polygons.is_empty() {
-            Err(Error::UnknownDimension)
+            None
         } else {
             let dim = polygons[0].dimension();
-            Ok(Self::new(polygons, dim))
+            Some(Self::new(polygons, dim))
         }
     }
 

src/types/polygon.rs

@@ -14,7 +14,6 @@
 
 use geo_traits::PolygonTrait;
 
-use crate::error::Error;
 use crate::to_wkt::write_polygon;
 use crate::tokenizer::PeekableTokens;
 use crate::types::linestring::LineString;
@@ -46,19 +45,17 @@ impl<T: WktNum> Polygon<T> {
     /// This will infer the dimension from the first line string, and will not validate that all
     /// line strings have the same dimension.
     ///
-    /// ## Errors
-    ///
-    /// If the input iterator is empty.
+    /// Returns `None` if the input iterator is empty.
     ///
     /// To handle empty input iterators, consider calling `unwrap_or` on the result and defaulting
     /// to an [empty][Self::empty] geometry with specified dimension.
-    pub fn from_rings(rings: impl IntoIterator<Item = LineString<T>>) -> Result<Self, Error> {
+    pub fn from_rings(rings: impl IntoIterator<Item = LineString<T>>) -> Option<Self> {
         let rings = rings.into_iter().collect::<Vec<_>>();
         if rings.is_empty() {
-            Err(Error::UnknownDimension)
+            None
         } else {
             let dim = rings[0].dimension();
-            Ok(Self::new(rings, dim))
+            Some(Self::new(rings, dim))
         }
     }