Initial commit

.gitignore

@@ -0,0 +1 @@
+/target

Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "stilts"
+version = "0.1.0"

Cargo.toml

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+[package]
+name = "stilts"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]

src/lib.rs

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+pub struct OutOfSpace;
+pub trait Push<T> {
+    fn push(&mut self, value: T) {
+        let _ = self.push_checked(value);
+    }
+
+    fn push_checked(&mut self, value: T) -> Result<(), OutOfSpace> {
+        self.push(value);
+
+        Ok(())
+    }
+}
+
+impl<T> Push<T> for () {
+    fn push(&mut self, _: T) {
+    }
+}
+
+impl<T> Push<T> for Vec<T> {
+    fn push(&mut self, value: T) {
+        self.push(value)
+    }
+}
+
+impl<T> Push<T> for Option<T> {
+    fn push(&mut self, value: T) {
+        *self = Some(value);
+    }
+
+    fn push_checked(&mut self, value: T) -> Result<(), OutOfSpace> {
+        match self {
+            Some(_) => Err(OutOfSpace),
+            None => {
+                self.push(value);
+                Ok(())
+            },
+        }
+    }
+}
+
+impl<'a, R, T> Push<T> for &'a mut R
+where
+    R: Push<T>,
+{
+    fn push(&mut self, value: T) {
+        (**self).push(value)
+    }
+
+    fn push_checked(&mut self, value: T) -> Result<(), OutOfSpace> {
+        (**self).push_checked(value)
+    }
+}