Reflection for castables

3 files changed, 66 insertions, 1 deletions

diff --git a/src/geom/mod.rs b/src/geom/mod.rs
index 3c7c2fc9..6161774b 100644
--- a/src/geom/mod.rs
+++ b/src/geom/mod.rs
@@ -21,6 +21,7 @@ mod rounded;
 mod scalar;
 mod sides;
 mod size;
+mod smart;
 mod stroke;
 mod transform;
 
@@ -43,6 +44,7 @@ pub use self::rounded::*;
 pub use self::scalar::*;
 pub use self::sides::*;
 pub use self::size::*;
+pub use self::smart::*;
 pub use self::stroke::*;
 pub use self::transform::*;
 
diff --git a/src/geom/smart.rs b/src/geom/smart.rs
new file mode 100644
index 00000000..d20bcdfe
--- /dev/null
+++ b/src/geom/smart.rs
@@ -0,0 +1,64 @@
+use super::*;
+
+/// A value that can be automatically determined.
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
+pub enum Smart<T> {
+    /// The value should be determined smartly based on the circumstances.
+    Auto,
+    /// A specific value.
+    Custom(T),
+}
+
+impl<T> Smart<T> {
+    /// Map the contained custom value with `f`.
+    pub fn map<F, U>(self, f: F) -> Smart<U>
+    where
+        F: FnOnce(T) -> U,
+    {
+        match self {
+            Self::Auto => Smart::Auto,
+            Self::Custom(x) => Smart::Custom(f(x)),
+        }
+    }
+
+    /// Keeps `self` if it contains a custom value, otherwise returns `other`.
+    pub fn or(self, other: Smart<T>) -> Self {
+        match self {
+            Self::Custom(x) => Self::Custom(x),
+            Self::Auto => other,
+        }
+    }
+
+    /// Returns the contained custom value or a provided default value.
+    pub fn unwrap_or(self, default: T) -> T {
+        match self {
+            Self::Auto => default,
+            Self::Custom(x) => x,
+        }
+    }
+
+    /// Returns the contained custom value or computes a default value.
+    pub fn unwrap_or_else<F>(self, f: F) -> T
+    where
+        F: FnOnce() -> T,
+    {
+        match self {
+            Self::Auto => f(),
+            Self::Custom(x) => x,
+        }
+    }
+
+    /// Returns the contained custom value or the default value.
+    pub fn unwrap_or_default(self) -> T
+    where
+        T: Default,
+    {
+        self.unwrap_or_else(T::default)
+    }
+}
+
+impl<T> Default for Smart<T> {
+    fn default() -> Self {
+        Self::Auto
+    }
+}
diff --git a/src/geom/stroke.rs b/src/geom/stroke.rs
index eae43c24..86191d33 100644
--- a/src/geom/stroke.rs
+++ b/src/geom/stroke.rs
@@ -1,5 +1,4 @@
 use super::*;
-use crate::model::Smart;
 
 /// A stroke of a geometric shape.
 #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]