Initial commit to save my work. Not finished yet.

.gitignore

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+/target
+/.idea/*

Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "rust_naming_conversion_examples"
+version = "0.1.0"

Cargo.toml

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+[package]
+name = "rust_naming_conversion_examples"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

src/main.rs

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+use std::path::Path;
+
+fn main() {
+
+}
+
+#[derive(Copy, Clone, Debug)]
+struct CopyObject<'a> {
+    pub val: &'a str,
+}
+
+struct AnObject {
+    pub val: String,
+}
+
+struct TheOtherObject {
+    pub val: Vec<u8>,
+}
+
+impl AnObject {
+
+    // as_ borrowed (&self) -> borrowed (&[u8])
+    fn as_bytes(&self) -> &[u8] {
+        // because the underlying data structure of a String is a Vec<u8>, the as_bytes actually just returns this as a borrowed value, really just making this a dumb proxy, but it shows us what we want: as_ is just a view into the underlying data structure: nothing is copied, nothing new is created, it only exposes the underlying data: free as in free beer because we are just returning something that point to something else: a reference
+        self.val.as_bytes()
+    }
+
+    // to_ borrowed (&self) -> borrowed (&[u8])
+    fn to_guarded_bytes(&self) -> Option<&[u8]> {
+        // this is really a dumb example, but it kind of proves the point: we convert our Target to a str. The input and output smells like the above as_ and the as_ is free, but this really isn't, because we are doing some expensive validation first
+        let mut is_valid = true;
+
+        for s in self.val.chars() {
+            if s > 'b' && s < 'w' {
+                is_valid = false;
+                break;
+            }
+        }
+
+        if is_valid {
+            return Some(self.val.as_bytes());
+        }
+
+        None
+    }
+
+    // to_ borrowed (&self) -> owned (TheOtherObject) (non-copy types)
+    fn to_guarded_object(&self) -> Option<TheOtherObject> {
+        // This performs our previous check, and if everything is fine, it converts our object to the new object, simply creating it, and making some more to_ calls. Really expensive, but no copy is made of `self`
+        let guarded_bytes = self.to_guarded_bytes();
+
+        match guarded_bytes {
+            Some(bytes) => {
+                Some(TheOtherObject {val: bytes.to_vec()})
+            },
+            None => None
+        }
+    }
+}
+
+impl<'a> CopyObject<'a> {
+
+    // to_ owned (self) -> owned (TheOtherObject) (copy types)
+    fn to_object(self) -> TheOtherObject {
+        // because self is not a reference, it is actually not consumed (likewise it isn't consumed when we do a &self ... yes we could do a &self here, but it kind of defeats the purpose of doing the example), but it is copied. The copy itself though is more expensive than just doing a reference. In our example, we are actually being quite expensive doing a to_vec conversion of our free as_ view
+
+        TheOtherObject { val: self.val.as_bytes().to_vec()}
+    }
+}
+
+// into_ owned -> owned (non-copy types)