src/compiler.rs

@@ -59,7 +59,7 @@ impl<'a> Chunk<'a> {
             spans: vec![],
             strings: vec![],
             keywords: vec![
-                "nil", "bool", "number", "keyword", "string", "tuple", "list", "dict", "box", "fn",
+                "nil", "bool", "number", "keyword", "string", "tuple", "list", "",
             ],
             nodes: vec![],
             ast: &ast.0,

src/main.rs

@@ -1,68 +0,0 @@
-use chumsky::{input::Stream, prelude::*};
-
-mod spans;
-
-mod lexer;
-use crate::lexer::lexer;
-
-mod parser;
-use crate::parser::parser;
-
-mod validator;
-
-mod compiler;
-use crate::compiler::Chunk;
-
-mod value;
-
-mod vm;
-use vm::Vm;
-
-pub fn run(src: &'static str) {
-    let (tokens, lex_errs) = lexer().parse(src).into_output_errors();
-    if !lex_errs.is_empty() {
-        println!("{:?}", lex_errs);
-        return;
-    }
-
-    let tokens = tokens.unwrap();
-
-    let (parse_result, parse_errors) = parser()
-        .parse(Stream::from_iter(tokens).map((0..src.len()).into(), |(t, s)| (t, s)))
-        .into_output_errors();
-    if !parse_errors.is_empty() {
-        println!("{:?}", parse_errors);
-        return;
-    }
-
-    let parsed = parse_result.unwrap();
-
-    let mut chunk = Chunk::new(&parsed, "test", src);
-    chunk.compile();
-    chunk.disassemble();
-
-    let mut vm = Vm::new(&chunk);
-    let result = vm.interpret();
-    let output = match result {
-        Ok(val) => val.show(&chunk),
-        Err(panic) => format!("{:?}", panic),
-    };
-    println!("{output}");
-}
-
-pub fn main() {
-    let src = "
-if false
-    then {
-        :foo
-        :bar
-        :baz
-    }
-    else {
-        1
-        2
-        3
-    }
-    ";
-    run(src);
-}

src/validator.rs

@@ -1,5 +1,5 @@
 use crate::parser::*;
-use crate::spans::{Span, Spanned};
+use crate::spans::Span;
 use crate::value::Value;
 use std::collections::{HashMap, HashSet};
 
@@ -143,13 +143,6 @@ impl<'a> Validator<'a> {
         }
     }
 
-    fn visit(&mut self, node: &'a Spanned<Ast>) {
-        let (expr, span) = node;
-        self.ast = expr;
-        self.span = *span;
-        self.validate();
-    }
-
     pub fn validate(&mut self) {
         use Ast::*;
         let root = self.ast;
@@ -186,13 +179,18 @@ impl<'a> Validator<'a> {
                 }
                 let to = self.locals.len();
                 let tailpos = self.status.tail_position;
-                for line in block.iter().take(block.len() - 1) {
+                for (expr, span) in block.iter().take(block.len() - 1) {
                     self.status.tail_position = false;
-                    self.visit(line);
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
 
+                let (expr, span) = block.last().unwrap();
+                self.ast = expr;
+                self.span = *span;
                 self.status.tail_position = tailpos;
-                self.visit(block.last().unwrap());
+                self.validate();
 
                 let block_bindings = self.locals.split_off(to);
 
@@ -209,12 +207,22 @@ impl<'a> Validator<'a> {
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
 
-                self.visit(cond.as_ref());
+                let (expr, span) = cond.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
 
                 // pass through tailpos only to then/else
                 self.status.tail_position = tailpos;
-                self.visit(then.as_ref());
-                self.visit(r#else.as_ref());
+                let (expr, span) = then.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
+
+                let (expr, span) = r#else.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
             }
             Tuple(members) => {
                 if members.is_empty() {
@@ -222,8 +230,10 @@ impl<'a> Validator<'a> {
                 }
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
-                for member in members {
-                    self.visit(member);
+                for (expr, span) in members {
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
                 self.status.tail_position = tailpos;
             }
@@ -234,8 +244,10 @@ impl<'a> Validator<'a> {
                 }
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
-                for arg in args {
-                    self.visit(arg);
+                for (expr, span) in args {
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
                 self.status.has_placeholder = false;
                 self.status.tail_position = tailpos;
@@ -255,21 +267,30 @@ impl<'a> Validator<'a> {
                 }
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
-                for member in list {
-                    self.visit(member);
+                for (expr, span) in list {
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
 
                 self.status.tail_position = tailpos;
             }
-            Pair(_, value) => self.visit(value.as_ref()),
+            Pair(_, value) => {
+                let (expr, span) = value.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
+            }
             Dict(dict) => {
                 if dict.is_empty() {
                     return;
                 }
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
-                for pair in dict {
-                    self.visit(pair)
+                for (expr, span) in dict {
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
                 self.status.tail_position = tailpos;
             }
@@ -278,16 +299,31 @@ impl<'a> Validator<'a> {
             // check arity against fn info if first term is word and second term is args
             Synthetic(first, second, rest) => {
                 match (&first.0, &second.0) {
-                    (Ast::Word(_), Ast::Keyword(_)) => self.visit(first.as_ref()),
+                    (Ast::Word(_), Ast::Keyword(_)) => {
+                        let (expr, span) = first.as_ref();
+                        self.ast = expr;
+                        self.span = *span;
+                        self.validate();
+                    }
                     (Ast::Keyword(_), Ast::Arguments(args)) => {
                         if args.len() != 1 {
                             self.err("called keywords may only take one argument".to_string())
                         }
-                        self.visit(second.as_ref());
+                        let (expr, span) = second.as_ref();
+                        self.ast = expr;
+                        self.span = *span;
+                        self.validate();
                     }
                     (Ast::Word(name), Ast::Arguments(args)) => {
-                        self.visit(first.as_ref());
-                        self.visit(second.as_ref());
+                        let (expr, span) = first.as_ref();
+                        self.ast = expr;
+                        self.span = *span;
+                        self.validate();
+
+                        let (expr, span) = second.as_ref();
+                        self.ast = expr;
+                        self.span = *span;
+                        self.validate();
 
                         //TODO: check arities of prelude fns, too
                         let fn_binding = self.bound(name);
@@ -301,20 +337,32 @@ impl<'a> Validator<'a> {
                     _ => unreachable!(),
                 }
                 for term in rest {
-                    self.visit(term);
+                    let (expr, span) = term;
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
             }
             WhenClause(cond, body) => {
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
-                self.visit(cond.as_ref());
-                //pass through tail position for when bodies
+                let (expr, span) = cond.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
+
                 self.status.tail_position = tailpos;
-                self.visit(body.as_ref());
+                let (expr, span) = body.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
             }
             When(clauses) => {
                 for clause in clauses {
-                    self.visit(clause);
+                    let (expr, span) = clause;
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
             }
 
@@ -326,30 +374,54 @@ impl<'a> Validator<'a> {
                 } else {
                     self.bind(name.to_string());
                 }
-                self.visit(boxed.as_ref());
+                let (expr, span) = boxed.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
             }
             Let(lhs, rhs) => {
-                self.visit(rhs.as_ref());
-                self.visit(lhs.as_ref());
+                let (expr, span) = rhs.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
+
+                let (expr, span) = lhs.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
             }
             MatchClause(pattern, guard, body) => {
                 let to = self.locals.len();
 
-                self.visit(pattern.as_ref());
+                let (patt, span) = pattern.as_ref();
+                self.ast = patt;
+                self.span = *span;
+                self.validate();
 
-                if let Some(guard) = guard.as_ref() {
-                    self.visit(guard);
+                if let Some((expr, span)) = guard.as_ref() {
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
 
-                self.visit(body.as_ref());
+                let (expr, span) = body.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
 
                 self.locals.truncate(to);
             }
             Match(scrutinee, clauses) => {
-                self.visit(scrutinee.as_ref());
+                let (expr, span) = scrutinee.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
 
                 for clause in clauses {
-                    self.visit(clause);
+                    let (expr, span) = clause;
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
             }
             FnDeclaration(name) => {
@@ -416,7 +488,10 @@ impl<'a> Validator<'a> {
             Panic(msg) => {
                 let tailpos = self.status.tail_position;
                 self.status.tail_position = false;
-                self.visit(msg.as_ref());
+                let (expr, span) = msg.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
                 self.status.tail_position = tailpos;
             }
             // TODO: fix the tail call here?
@@ -425,23 +500,39 @@ impl<'a> Validator<'a> {
                     return self.err("do expressions must have at least two terms".to_string());
                 }
                 for term in terms.iter().take(terms.len() - 1) {
-                    self.visit(term);
+                    let (expr, span) = term;
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
-                let last = terms.last().unwrap();
-                self.visit(last);
-                if matches!(last.0, Ast::Recur(_)) {
+
+                let (expr, span) = terms.last().unwrap();
+                self.ast = expr;
+                self.span = *span;
+                if matches!(expr, Ast::Recur(_)) {
                     self.err("`recur` may not be used in `do` forms".to_string());
                 }
+                self.validate();
             }
             Repeat(times, body) => {
                 self.status.tail_position = false;
-                self.visit(times.as_ref());
-                self.visit(body.as_ref());
+                let (expr, span) = times.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
+
+                let (expr, span) = body.as_ref();
+                self.ast = expr;
+                self.span = *span;
+                self.validate();
             }
             Loop(with, body) => {
-                self.visit(with.as_ref());
+                let (expr, span) = with.as_ref();
+                self.span = *span;
+                self.ast = expr;
+                self.validate();
 
-                let Ast::Tuple(input) = &with.0 else {
+                let Ast::Tuple(input) = expr else {
                     unreachable!()
                 };
 
@@ -497,7 +588,10 @@ impl<'a> Validator<'a> {
 
                 self.status.tail_position = false;
                 for arg in args {
-                    self.visit(arg);
+                    let (expr, span) = arg;
+                    self.ast = expr;
+                    self.span = *span;
+                    self.validate();
                 }
             }
             WordPattern(name) => match self.bound(name) {
@@ -560,15 +654,25 @@ impl<'a> Validator<'a> {
                     return;
                 }
                 for term in terms.iter().take(terms.len() - 1) {
-                    self.visit(term);
+                    let (patt, span) = term;
+                    self.ast = patt;
+                    self.span = *span;
+                    self.validate();
                 }
 
                 self.status.last_term = true;
-                let last = terms.last().unwrap();
-                self.visit(last);
+                let (patt, span) = terms.last().unwrap();
+                self.ast = patt;
+                self.span = *span;
+                self.validate();
                 self.status.last_term = false;
             }
-            PairPattern(_, patt) => self.visit(patt.as_ref()),
+            PairPattern(_, patt) => {
+                let (patt, span) = patt.as_ref();
+                self.ast = patt;
+                self.span = *span;
+                self.validate();
+            }
             // terminals can never be invalid
             Nil | Boolean(_) | Number(_) | Keyword(_) | String(_) => (),
             // terminal patterns can never be invalid

src/vm.rs

@@ -1,87 +0,0 @@
-use crate::compiler::{Chunk, Op};
-use crate::parser::Ast;
-use crate::spans::Spanned;
-use crate::value::Value;
-use chumsky::prelude::SimpleSpan;
-use num_traits::FromPrimitive;
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct Panic {
-    pub input: &'static str,
-    pub src: &'static str,
-    pub msg: String,
-    pub span: SimpleSpan,
-    pub trace: Vec<Trace>,
-    pub extra: String,
-}
-
-#[derive(Debug, Clone, PartialEq)]
-pub struct Trace {
-    pub callee: Spanned<Ast>,
-    pub caller: Spanned<Ast>,
-    pub function: Value,
-    pub arguments: Value,
-    pub input: &'static str,
-    pub src: &'static str,
-}
-
-pub struct Vm<'a> {
-    pub stack: Vec<Value>,
-    pub chunk: &'a Chunk<'a>,
-    pub ip: usize,
-    pub bindings: Vec<(u8, usize)>,
-}
-
-impl<'a> Vm<'a> {
-    pub fn new(chunk: &'a Chunk) -> Vm<'a> {
-        Vm {
-            chunk,
-            stack: vec![],
-            ip: 0,
-            bindings: vec![],
-        }
-    }
-
-    pub fn push(&mut self, value: Value) {
-        self.stack.push(value);
-    }
-
-    pub fn pop(&mut self) -> Value {
-        self.stack.pop().unwrap()
-    }
-
-    pub fn interpret(&mut self) -> Result<Value, Panic> {
-        let byte = self.chunk.bytecode[self.ip];
-        let op = Op::from_u8(byte).unwrap();
-        use Op::*;
-        match op {
-            Return => Ok(self.stack.pop().unwrap()),
-            Constant => {
-                let const_idx = self.chunk.bytecode[self.ip + 1];
-                let value = self.chunk.constants[const_idx as usize].clone();
-                self.push(value);
-                self.ip += 2;
-                self.interpret()
-            }
-            Jump => {
-                let jump_len = self.chunk.bytecode[self.ip + 1];
-                self.ip += jump_len as usize;
-                self.interpret()
-            }
-            JumpIfFalse => {
-                let jump_len = self.chunk.bytecode[self.ip + 1];
-                let cond = self.stack.pop().unwrap();
-                match cond {
-                    Value::Nil | Value::False => {
-                        self.ip += jump_len as usize + 2;
-                        self.interpret()
-                    }
-                    _ => {
-                        self.ip += 2;
-                        self.interpret()
-                    }
-                }
-            }
-        }
-    }
-}