fix(argus): parse errors

argus/Cargo.toml

@@ -14,6 +14,7 @@ ariadne = { version = "0.3.0", optional = true }
 chumsky = { version = "1.0.0-alpha.6", features = ["default", "label"] }
 derive_more = "0.99.17"
 enum_dispatch = "0.3.12"
+hashbrown = "0.14.1"
 itertools = "0.11"
 num-traits = "0.2.16"
 paste = "1.0.14"

argus/src/core/expr.rs

@@ -1,6 +1,6 @@
 //! Expression tree for Argus specifications
 
-use std::collections::HashSet;
+use hashbrown::HashMap;
 
 mod bool_expr;
 pub mod iter;
@@ -13,7 +13,7 @@ pub use num_expr::*;
 pub use traits::*;
 
 use self::iter::AstIter;
-use crate::{ArgusResult, Error};
+use crate::{ArgusResult, Error, Type};
 
 /// A trait representing expressions
 #[enum_dispatch]
@@ -155,7 +155,7 @@ pub enum Expr {
 /// definitions for variables.
 #[derive(Clone, Debug, Default)]
 pub struct ExprBuilder {
-    declarations: HashSet<String>,
+    pub(crate) declarations: HashMap<String, Type>,
 }
 
 impl ExprBuilder {
@@ -188,37 +188,33 @@ impl ExprBuilder {
 
     /// Declare a boolean variable
     pub fn bool_var(&mut self, name: String) -> ArgusResult<BoolExpr> {
-        if self.declarations.insert(name.clone()) {
+        match self.declarations.insert(name.clone(), Type::Bool) {
-            Ok((BoolVar { name }).into())
+            None | Some(Type::Bool) => Ok((BoolVar { name }).into()),
-        } else {
+            _ => Err(Error::IdentifierRedeclaration),
-            Err(Error::IdentifierRedeclaration)
         }
     }
 
     /// Declare a integer variable
     pub fn int_var(&mut self, name: String) -> ArgusResult<NumExpr> {
-        if self.declarations.insert(name.clone()) {
+        match self.declarations.insert(name.clone(), Type::Int) {
-            Ok((IntVar { name }).into())
+            None | Some(Type::Int) => Ok((IntVar { name }).into()),
-        } else {
+            _ => Err(Error::IdentifierRedeclaration),
-            Err(Error::IdentifierRedeclaration)
         }
     }
 
     /// Declare a unsigned integer variable
     pub fn uint_var(&mut self, name: String) -> ArgusResult<NumExpr> {
-        if self.declarations.insert(name.clone()) {
+        match self.declarations.insert(name.clone(), Type::UInt) {
-            Ok((UIntVar { name }).into())
+            None | Some(Type::UInt) => Ok((UIntVar { name }).into()),
-        } else {
+            _ => Err(Error::IdentifierRedeclaration),
-            Err(Error::IdentifierRedeclaration)
         }
     }
 
     /// Declare a floating point variable
     pub fn float_var(&mut self, name: String) -> ArgusResult<NumExpr> {
-        if self.declarations.insert(name.clone()) {
+        match self.declarations.insert(name.clone(), Type::Float) {
-            Ok((FloatVar { name }).into())
+            None | Some(Type::Float) => Ok((FloatVar { name }).into()),
-        } else {
+            _ => Err(Error::IdentifierRedeclaration),
-            Err(Error::IdentifierRedeclaration)
         }
     }
 

argus/src/lib.rs

@@ -16,8 +16,39 @@ pub use crate::core::{expr, signals};
 pub use crate::parser::parse_str;
 pub use crate::semantics::{BooleanSemantics, QuantitativeSemantics, Trace};
 
+#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
+pub(crate) enum Type {
+    #[default]
+    Unknown,
+    Bool,
+    UInt,
+    Int,
+    Float,
+}
+
+impl Type {
+    /// Get the lowest common supertype for the given types to a common
+    fn get_common_cast(self, other: Self) -> Self {
+        use Type::*;
+        match (self, other) {
+            (Unknown, other) | (other, Unknown) => other,
+            (Bool, ty) | (ty, Bool) => ty,
+            (UInt, Int) => Float,
+            (UInt, Float) => Float,
+            (Int, UInt) => Float,
+            (Int, Float) => Float,
+            (Float, UInt) => Float,
+            (Float, Int) => Float,
+            (lhs, rhs) => {
+                assert_eq!(lhs, rhs);
+                rhs
+            }
+        }
+    }
+}
+
 /// Errors generated by all Argus components.
-#[derive(Error, Debug)]
+#[derive(Error, Debug, PartialEq, Eq)]
 pub enum Error {
     /// An identifier has been redeclared in a specification.
     ///

argus/src/parser/lexer.rs

@@ -87,13 +87,13 @@ pub fn lexer<'src>() -> impl Parser<'src, &'src str, Output<'src>, Error<'src>>
     // A parser for numbers
     let digits = text::digits(10).to_slice();
 
-    let frac = just('.').then(digits);
+    let frac = just('.').then(digits.or_not());
 
     let exp = just('e').or(just('E')).then(one_of("+-").or_not()).then(digits);
 
     let floating_number = just('-')
         .or_not()
-        .then(digits)
+        .then(digits.or_not())
         .then(choice((frac.then(exp).to_slice(), frac.to_slice(), exp.to_slice())))
         // .then(frac.or_not())
         // .then(exp.or_not())
@@ -104,13 +104,9 @@ pub fn lexer<'src>() -> impl Parser<'src, &'src str, Output<'src>, Error<'src>>
     let signed_int = one_of("+-")
         // .or_not()
         .then(digits)
-        .then(frac.not().or(exp.not()))
         .to_slice()
         .map(|s: &str| Token::Int(s.parse().unwrap()));
-    let unsigned_int = digits
+    let unsigned_int = digits.to_slice().map(|s: &str| Token::UInt(s.parse().unwrap()));
-        .then(frac.not().or(exp.not()))
-        .to_slice()
-        .map(|s: &str| Token::UInt(s.parse().unwrap()));
 
     let number = choice((floating_number, signed_int, unsigned_int));
 

argus/src/parser/mod.rs

@@ -10,6 +10,8 @@ use chumsky::prelude::Rich;
 use lexer::{lexer, Token};
 use syntax::{parser, Expr, Interval};
 
+use crate::Type;
+
 /// Parse a string expression into a concrete Argus expression.
 pub fn parse_str(src: &str) -> Result<crate::core::expr::Expr, Vec<Rich<'_, String>>> {
     use chumsky::prelude::{Input, Parser};
@@ -79,26 +81,26 @@ fn ast_to_expr<'tokens, 'src: 'tokens>(
     ctx: &mut ExprBuilder,
 ) -> Result<crate::core::expr::Expr, Rich<'tokens, Token<'src>, lexer::Span>> {
     match ast {
-        Expr::Error => unreachable!("Errors should have been caught by parser"),
+        Expr::Error => Err(Rich::custom(span, "Errors should have been caught by parser")),
         Expr::Bool(value) => Ok(ctx.bool_const(*value).into()),
         Expr::Int(value) => Ok(ctx.int_const(*value).into()),
         Expr::UInt(value) => Ok(ctx.uint_const(*value).into()),
         Expr::Float(value) => Ok(ctx.float_const(*value).into()),
         Expr::Var { name, kind } => match kind {
-            syntax::Type::Unknown => Err(Rich::custom(span, "All variables must have defined type by now.")),
+            Type::Unknown => Err(Rich::custom(span, "All variables must have defined type by now.")),
-            syntax::Type::Bool => ctx
+            Type::Bool => ctx
                 .bool_var(name.to_string())
                 .map(|var| var.into())
                 .map_err(|err| Rich::custom(span, err.to_string())),
-            syntax::Type::UInt => ctx
+            Type::UInt => ctx
                 .uint_var(name.to_string())
                 .map(|var| var.into())
                 .map_err(|err| Rich::custom(span, err.to_string())),
-            syntax::Type::Int => ctx
+            Type::Int => ctx
                 .int_var(name.to_string())
                 .map(|var| var.into())
                 .map_err(|err| Rich::custom(span, err.to_string())),
-            syntax::Type::Float => ctx
+            Type::Float => ctx
                 .float_var(name.to_string())
                 .map(|var| var.into())
                 .map_err(|err| Rich::custom(span, err.to_string())),

argus/src/parser/syntax.rs

@@ -3,40 +3,10 @@ use chumsky::prelude::*;
 use chumsky::Parser;
 
 use super::lexer::{Span, Token};
-
+use crate::Type;
-#[derive(Debug, Clone, Copy, Default, PartialEq, Eq)]
-pub enum Type {
-    #[default]
-    Unknown,
-    Bool,
-    UInt,
-    Int,
-    Float,
-}
-
-impl Type {
-    /// Get the lowest common supertype for the given types to a common
-    fn get_common_cast(self, other: Self) -> Self {
-        use Type::*;
-        match (self, other) {
-            (Unknown, other) | (other, Unknown) => other,
-            (Bool, ty) | (ty, Bool) => ty,
-            (UInt, Int) => Float,
-            (UInt, Float) => Float,
-            (Int, UInt) => Float,
-            (Int, Float) => Float,
-            (Float, UInt) => Float,
-            (Float, Int) => Float,
-            (lhs, rhs) => {
-                assert_eq!(lhs, rhs);
-                rhs
-            }
-        }
-    }
-}
 
 #[derive(Debug, Clone, PartialEq)]
-pub struct Interval<'src> {
+pub(crate) struct Interval<'src> {
     pub a: Option<Box<Spanned<Expr<'src>>>>,
     pub b: Option<Box<Spanned<Expr<'src>>>>,
 }
@@ -98,7 +68,7 @@ impl BinaryOps {
 }
 
 #[derive(Debug, Clone, PartialEq)]
-pub enum Expr<'src> {
+pub(crate) enum Expr<'src> {
     Error,
     Bool(bool),
     Int(i64),
@@ -258,7 +228,7 @@ fn num_expr_parser<'tokens, 'src: 'tokens>(
     })
 }
 
-pub fn parser<'tokens, 'src: 'tokens>(
+pub(crate) fn parser<'tokens, 'src: 'tokens>(
 ) -> impl Parser<'tokens, ParserInput<'tokens, 'src>, Spanned<Expr<'src>>, Error<'tokens, 'src>> + Clone {
     let interval = {
         let num_literal = select! {
@@ -327,6 +297,7 @@ pub fn parser<'tokens, 'src: 'tokens>(
                 [],
                 |span| (Expr::Error, span),
             )))
+            .or(expr)
             .boxed();
 
         let not_op = just(Token::Not)