cl-interpret: Give the interpreter a little love

And stop copying strings around.

compiler/cl-interpret/src/builtin.rs

@@ -6,7 +6,10 @@ use super::{
     temp_type_impl::ConValue,
     BuiltIn, Callable,
 };
-use std::io::{stdout, Write};
+use std::{
+    io::{stdout, Write},
+    rc::Rc,
+};
 
 builtins! {
     const MISC;
@@ -65,7 +68,7 @@ builtins! {
         Ok(match (lhs, rhs) {
             (ConValue::Empty, ConValue::Empty) => ConValue::Empty,
             (ConValue::Int(a), ConValue::Int(b)) => ConValue::Int(a + b),
-            (ConValue::String(a), ConValue::String(b)) => ConValue::String(a.to_string() + b),
+            (ConValue::String(a), ConValue::String(b)) => (a.to_string() + b).into(),
             _ => Err(Error::TypeError)?
         })
     }
@@ -184,6 +187,12 @@ builtins! {
             _ => Err(Error::TypeError)?,
         })
     }
+    pub fn deref(tail) -> IResult<ConValue> {
+        Ok(match tail {
+            ConValue::Ref(v) => Rc::as_ref(v).clone(),
+            _ => tail.clone(),
+        })
+    }
 }
 
 /// Turns an argument slice into an array with the (inferred) correct number of elements

compiler/cl-interpret/src/interpret.rs

@@ -5,7 +5,7 @@
 //! meaningless to get a pointer to one, and would be undefined behavior to dereference a pointer to
 //! one in any situation.
 
-use std::borrow::Borrow;
+use std::{borrow::Borrow, rc::Rc};
 
 use super::*;
 use cl_ast::*;
@@ -40,18 +40,21 @@ impl Interpret for Item {
     }
 }
 impl Interpret for Alias {
-    fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
+    fn interpret(&self, _env: &mut Environment) -> IResult<ConValue> {
-        todo!("Interpret type alias in {env}")
+        println!("TODO: {self}");
+        Ok(ConValue::Empty)
     }
 }
 impl Interpret for Const {
-    fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
+    fn interpret(&self, _env: &mut Environment) -> IResult<ConValue> {
-        todo!("interpret const in {env}")
+        println!("TODO: {self}");
+        Ok(ConValue::Empty)
     }
 }
 impl Interpret for Static {
-    fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
+    fn interpret(&self, _env: &mut Environment) -> IResult<ConValue> {
-        todo!("interpret static in {env}")
+        println!("TODO: {self}");
+        Ok(ConValue::Empty)
     }
 }
 impl Interpret for Module {
@@ -71,18 +74,22 @@ impl Interpret for Function {
     }
 }
 impl Interpret for Struct {
-    fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
+    fn interpret(&self, _env: &mut Environment) -> IResult<ConValue> {
-        todo!("Interpret structs in {env}")
+        println!("TODO: {self}");
+        Ok(ConValue::Empty)
     }
 }
 impl Interpret for Enum {
-    fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
+    fn interpret(&self, _env: &mut Environment) -> IResult<ConValue> {
-        todo!("Interpret enums in {env}")
+        println!("TODO: {self}");
+        Ok(ConValue::Empty)
     }
 }
 impl Interpret for Impl {
     fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
-        todo!("Enter a struct's namespace and insert function definitions into it in {env}");
+        println!("TODO: {self}");
+        let Self { target: _, body } = self;
+        body.interpret(env)
     }
 }
 impl Interpret for Stmt {
@@ -229,24 +236,24 @@ impl Interpret for Binary {
         }
         let tail = tail.interpret(env)?;
         match kind {
-            BinaryKind::Mul => env.call("mul", &[head, tail]),
+            BinaryKind::Lt => head.lt(&tail),
-            BinaryKind::Div => env.call("div", &[head, tail]),
+            BinaryKind::LtEq => head.lt_eq(&tail),
-            BinaryKind::Rem => env.call("rem", &[head, tail]),
+            BinaryKind::Equal => head.eq(&tail),
-            BinaryKind::Add => env.call("add", &[head, tail]),
+            BinaryKind::NotEq => head.neq(&tail),
-            BinaryKind::Sub => env.call("sub", &[head, tail]),
+            BinaryKind::GtEq => head.gt_eq(&tail),
-            BinaryKind::Shl => env.call("shl", &[head, tail]),
+            BinaryKind::Gt => head.gt(&tail),
-            BinaryKind::Shr => env.call("shr", &[head, tail]),
+            BinaryKind::RangeExc => head.range_exc(tail),
-            BinaryKind::BitAnd => env.call("and", &[head, tail]),
+            BinaryKind::RangeInc => head.range_inc(tail),
-            BinaryKind::BitOr => env.call("or", &[head, tail]),
+            BinaryKind::BitAnd => head & tail,
-            BinaryKind::BitXor => env.call("xor", &[head, tail]),
+            BinaryKind::BitOr => head | tail,
-            BinaryKind::RangeExc => env.call("range_exc", &[head, tail]),
+            BinaryKind::BitXor => head ^ tail,
-            BinaryKind::RangeInc => env.call("range_inc", &[head, tail]),
+            BinaryKind::Shl => head << tail,
-            BinaryKind::Lt => env.call("lt", &[head, tail]),
+            BinaryKind::Shr => head >> tail,
-            BinaryKind::LtEq => env.call("lt_eq", &[head, tail]),
+            BinaryKind::Add => head + tail,
-            BinaryKind::Equal => env.call("eq", &[head, tail]),
+            BinaryKind::Sub => head - tail,
-            BinaryKind::NotEq => env.call("neq", &[head, tail]),
+            BinaryKind::Mul => head * tail,
-            BinaryKind::GtEq => env.call("gt_eq", &[head, tail]),
+            BinaryKind::Div => head / tail,
-            BinaryKind::Gt => env.call("gt", &[head, tail]),
+            BinaryKind::Rem => head % tail,
             BinaryKind::Dot => todo!("search within a type's namespace!"),
             BinaryKind::Call => match tail {
                 ConValue::Empty => head.call(env, &[]),
@@ -255,6 +262,36 @@ impl Interpret for Binary {
             },
             _ => Ok(head),
         }
+
+        // // Temporarily disabled, to avoid function dispatch overhead while I screw around
+        // // Not like it helped much in the first place!
+        // match kind {
+        //     BinaryKind::Mul => env.call("mul", &[head, tail]),
+        //     BinaryKind::Div => env.call("div", &[head, tail]),
+        //     BinaryKind::Rem => env.call("rem", &[head, tail]),
+        //     BinaryKind::Add => env.call("add", &[head, tail]),
+        //     BinaryKind::Sub => env.call("sub", &[head, tail]),
+        //     BinaryKind::Shl => env.call("shl", &[head, tail]),
+        //     BinaryKind::Shr => env.call("shr", &[head, tail]),
+        //     BinaryKind::BitAnd => env.call("and", &[head, tail]),
+        //     BinaryKind::BitOr => env.call("or", &[head, tail]),
+        //     BinaryKind::BitXor => env.call("xor", &[head, tail]),
+        //     BinaryKind::RangeExc => env.call("range_exc", &[head, tail]),
+        //     BinaryKind::RangeInc => env.call("range_inc", &[head, tail]),
+        //     BinaryKind::Lt => env.call("lt", &[head, tail]),
+        //     BinaryKind::LtEq => env.call("lt_eq", &[head, tail]),
+        //     BinaryKind::Equal => env.call("eq", &[head, tail]),
+        //     BinaryKind::NotEq => env.call("neq", &[head, tail]),
+        //     BinaryKind::GtEq => env.call("gt_eq", &[head, tail]),
+        //     BinaryKind::Gt => env.call("gt", &[head, tail]),
+        //     BinaryKind::Dot => todo!("search within a type's namespace!"),
+        //     BinaryKind::Call => match tail {
+        //         ConValue::Empty => head.call(env, &[]),
+        //         ConValue::Tuple(args) => head.call(env, &args),
+        //         _ => Err(Error::TypeError),
+        //     },
+        //     _ => Ok(head),
+        // }
     }
 }
 
@@ -291,7 +328,7 @@ impl Interpret for Path {
         if parts.len() == 1 {
             match parts.last().expect("parts should not be empty") {
                 PathPart::SuperKw | PathPart::SelfKw => todo!("Path navigation"),
-                PathPart::Ident(Identifier(s)) => env.get(s).cloned(),
+                PathPart::Ident(Identifier(s)) => env.get(s),
             }
         } else {
             todo!("Path navigation!")
@@ -316,7 +353,7 @@ impl Interpret for Array {
         for expr in values {
             out.push(expr.interpret(env)?)
         }
-        Ok(ConValue::Array(out))
+        Ok(ConValue::Array(out.into()))
     }
 }
 impl Interpret for ArrayRep {
@@ -327,14 +364,21 @@ impl Interpret for ArrayRep {
             _ => Err(Error::TypeError)?,
         };
         let value = value.interpret(env)?;
-        Ok(ConValue::Array(vec![value; repeat as usize]))
+        Ok(ConValue::Array(vec![value; repeat as usize].into()))
     }
 }
 impl Interpret for AddrOf {
     fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
         let Self { count: _, mutable: _, expr } = self;
-        // this is stupid
+        match expr.as_ref() {
-        todo!("Create reference\nfrom expr: {expr}\nin env:\n{env}\n")
+            ExprKind::Index(_) => todo!("AddrOf array index"),
+            // ExprKind::Path(Path { absolute: false, parts }) => match parts.as_slice() {
+            //     [PathPart::Ident(Identifier(id))] => env.get_ref(id),
+            //     _ => todo!("Path traversal in addrof"),
+            // },
+            ExprKind::Path(_) => todo!("Path traversal in addrof"),
+            _ => Ok(ConValue::Ref(Rc::new(expr.interpret(env)?))),
+        }
     }
 }
 impl Interpret for Block {
@@ -357,13 +401,15 @@ impl Interpret for Group {
 impl Interpret for Tuple {
     fn interpret(&self, env: &mut Environment) -> IResult<ConValue> {
         let Self { exprs } = self;
-        Ok(ConValue::Tuple(exprs.iter().try_fold(
+        Ok(ConValue::Tuple(
-            vec![],
+            exprs
-            |mut out, element| {
+                .iter()
+                .try_fold(vec![], |mut out, element| {
                     out.push(element.interpret(env)?);
                     Ok(out)
-            },
+                })?
-        )?))
+                .into(),
+        ))
     }
 }
 impl Interpret for Loop {

compiler/cl-interpret/src/lib.rs

@@ -30,7 +30,7 @@ pub mod temp_type_impl {
         function::Function,
         BuiltIn, Callable, Environment,
     };
-    use std::ops::*;
+    use std::{ops::*, rc::Rc};
 
     type Integer = isize;
 
@@ -50,11 +50,13 @@ pub mod temp_type_impl {
         /// A unicode character
         Char(char),
         /// A string
-        String(String),
+        String(Rc<str>),
+        /// A reference
+        Ref(Rc<ConValue>),
         /// An Array
-        Array(Vec<ConValue>),
+        Array(Rc<[ConValue]>),
         /// A tuple
-        Tuple(Vec<ConValue>),
+        Tuple(Rc<[ConValue]>),
         /// An exclusive range
         RangeExc(Integer, Integer),
         /// An inclusive range
@@ -166,6 +168,7 @@ pub mod temp_type_impl {
         char => ConValue::Char,
         &str => ConValue::String,
         String => ConValue::String,
+        Rc<str> => ConValue::String,
         Function => ConValue::Function,
         Vec<ConValue> => ConValue::Tuple,
         &'static dyn BuiltIn => ConValue::BuiltIn,
@@ -199,7 +202,7 @@ pub mod temp_type_impl {
         Add: add = [
             (ConValue::Empty, ConValue::Empty) => ConValue::Empty,
             (ConValue::Int(a), ConValue::Int(b)) => ConValue::Int(a + b),
-            (ConValue::String(a), ConValue::String(b)) => ConValue::String(a + &b),
+            (ConValue::String(a), ConValue::String(b)) => (a.to_string() + &b).into(),
             _ => Err(Error::TypeError)?
             ]
         BitAnd: bitand = [
@@ -259,6 +262,7 @@ pub mod temp_type_impl {
                 ConValue::Bool(v) => v.fmt(f),
                 ConValue::Char(v) => v.fmt(f),
                 ConValue::String(v) => v.fmt(f),
+                ConValue::Ref(v) => write!(f, "&{v}"),
                 ConValue::Array(array) => {
                     '['.fmt(f)?;
                     for (idx, element) in array.iter().enumerate() {
@@ -296,13 +300,15 @@ pub mod interpret;
 
 pub mod function {
     //! Represents a block of code which lives inside the Interpreter
+
     use super::{Callable, ConValue, Environment, Error, IResult, Interpret};
     use cl_ast::{Function as FnDecl, Identifier, Param};
+    use std::rc::Rc;
     /// Represents a block of code which persists inside the Interpreter
     #[derive(Clone, Debug)]
     pub struct Function {
         /// Stores the contents of the function declaration
-        decl: Box<FnDecl>,
+        decl: Rc<FnDecl>,
         // /// Stores the enclosing scope of the function
         // env: Box<Environment>,
     }
@@ -322,19 +328,17 @@ pub mod function {
             name
         }
         fn call(&self, env: &mut Environment, args: &[ConValue]) -> IResult<ConValue> {
-            let FnDecl { name: Identifier(name), bind: declargs, body, sign: _ } = &*self.decl;
+            let FnDecl { name: Identifier(name), bind, body, sign: _ } = &*self.decl;
             // Check arg mapping
-            if args.len() != declargs.len() {
+            if args.len() != bind.len() {
-                return Err(Error::ArgNumber { want: declargs.len(), got: args.len() });
+                return Err(Error::ArgNumber { want: bind.len(), got: args.len() });
             }
             let Some(body) = body else {
                 return Err(Error::NotDefined(name.into()));
             };
             // TODO: completely refactor data storage
             let mut frame = env.frame("fn args");
-            for (Param { mutability: _, name: Identifier(name) }, value) in
+            for (Param { mutability: _, name: Identifier(name) }, value) in bind.iter().zip(args) {
-                declargs.iter().zip(args)
-            {
                 frame.insert(name, Some(value.clone()));
             }
             match body.interpret(&mut frame) {
@@ -364,10 +368,12 @@ pub mod env {
         ops::{Deref, DerefMut},
     };
 
+    type StackFrame = HashMap<String, Option<ConValue>>;
+
     /// Implements a nested lexical scope
     #[derive(Clone, Debug)]
     pub struct Environment {
-        frames: Vec<(HashMap<String, Option<ConValue>>, &'static str)>,
+        frames: Vec<(StackFrame, &'static str)>,
     }
 
     impl Display for Environment {
@@ -444,10 +450,10 @@ pub mod env {
         /// Resolves a variable immutably.
         ///
         /// Returns a reference to the variable's contents, if it is defined and initialized.
-        pub fn get(&self, id: &str) -> IResult<&ConValue> {
+        pub fn get(&self, id: &str) -> IResult<ConValue> {
             for (frame, _) in self.frames.iter().rev() {
                 match frame.get(id) {
-                    Some(Some(var)) => return Ok(var),
+                    Some(Some(var)) => return Ok(var.clone()),
                     Some(None) => return Err(Error::NotInitialized(id.into())),
                     _ => (),
                 }

sample-code/fib.cl

@@ -1,16 +1,29 @@
 // Calculate Fibonacci numbers
 
 fn main() {
+    for num in 0..=30 {
+        print("fib(", num, ") = ", fib_iterative(num))
+    }
     for num in 0..=30 {
         print("fib(", num, ") = ", fib(num))
     }
 }
 
-/// Implements the classic recursive definition of fib()
+/// The classic recursive definition of fib()
 fn fib(a: i64) -> i64 {
     if a > 1 {
         fib(a - 1) + fib(a - 2)
-    } else {
+    } else a
-        1
 }
+
+/// The classic iterative algorithm for fib()
+fn fib_iterative(n: i64) -> i64 {
+    let mut a = 0;
+    let mut b = 1;
+    let mut c = 1;
+    for _ in 0..n {
+        a = b;
+        b = c;
+        c = a + b;
+    } else a
 }

sample-code/fizzbuzz.cl

@@ -1,11 +1,11 @@
 // FizzBuzz, using the unstable variadic-`print` builtin
 
 fn main() {
-    fizz_buzz(10, 20)
+    fizzbuzz(10, 20)
 }
 
 // Outputs FizzBuzz for numbers between `start` and `end`, inclusive
-fn fizz_buzz(start: i128, end: i128) {
+fn fizzbuzz(start: i128, end: i128) {
     for x in start..=end {
         print(if x % 15 == 0 {
             "FizzBuzz"