fix(lang/rust): remove more advanced interface example

Signed-off-by: Victor Adossi <[email protected]>

Author: vados-cosmonic

component-model/src/language-support/rust.md

@@ -122,73 +122,6 @@ $ cargo run --release -- 1 2 ../add/target/wasm32-wasip1/release/add.wasm
 1 + 2 = 3
 ```
 
-## Exporting an interface with `cargo component`
-
-While it is possible to export a raw function, it is a best practice to export an interface, similar to the [sample `adder` world][add-wit]. 
-This often makes it easier to comply with an existing specification or to capture a set of functions and types 
-that tend to go together. 
-
-For example, consider the following changes to the `add` interface in the `adder` world:
-
-```wit
-package docs:[email protected];
-
-
-interface add {
-    variant operand { 
-        unsigned32(u32)
-        signed32(s32)
-        zero,
-    }
-
-    add: func(x: operand, y: operand) -> result<operand, string>;
-}
-
-world adder {
-    export add;
-}
-```
-
-This would be implemented with the following Rust code:
-
-```rust
-#[allow(warnings)]
-mod bindings;
-
-use bindings::exports::docs::adder::add::{Guest, Operand};
-
-struct Component;
-
-impl Guest for Component {
-    fn add(x: Operand, y: Operand) -> Result<Operand, String> {
-        let x = convert_operand(x);
-        let y = convert_operand(y);
-        match x + y {
-            v if v == 0 => Ok(Operand::Zero),
-            v if v < 0 => i32::try_from(v)
-                .map_err(|e| format!("unexpectedly invalid u32: {e}"))
-                .map(Operand::Signed32),
-            v => u32::try_from(v)
-                .map_err(|e| format!("unexpectedly invalid u32: {e}"))
-                .map(Operand::Unsigned32),
-        }
-    }
-}
-
-fn convert_operand(operand: Operand) -> i64 {
-    match operand {
-        Operand::Unsigned32(v) => v as i64,
-        Operand::Signed32(v) => v as i64,
-        Operand::Zero => 0,
-    }
-}
-
-bindings::export!(Component with_types_in bindings);
-```
-
-The code above is unlikely to appear in real interfaces; however, it shows the more common case of an interface 
-including types that are meant to be used *with* the interface in question. 
-
 ## Importing an interface with `cargo component`
 
 The world file (`wit/world.wit`) generated for you by `cargo component new --lib` doesn't specify any imports.