Parsing improvements 🧽

- Simplified scanner code
- Peek eagerly
- Skip whitespace and comments automatically in header mode
- Parse simple block expressions
- Move literal definitions into expression module
- Raw resolving tests

3 files changed, 54 insertions, 59 deletions

diff --git a/src/syntax/expr.rs b/src/syntax/expr.rs
index 91f4053c..4c6ce872 100644
--- a/src/syntax/expr.rs
+++ b/src/syntax/expr.rs
@@ -1,6 +1,9 @@
 //! Expressions.
 
 use super::*;
+use crate::color::RgbaColor;
+use crate::eval::DictKey;
+use crate::geom::Unit;
 
 /// An expression.
 #[derive(Debug, Clone, PartialEq)]
@@ -33,7 +36,7 @@ pub struct ExprUnary {
     /// The operator: `-`.
     pub op: Spanned<UnOp>,
     /// The expression to operator on: `x`.
-    pub expr: Spanned<Box<Expr>>,
+    pub expr: Box<Spanned<Expr>>,
 }
 
 /// A unary operator.
@@ -47,11 +50,11 @@ pub enum UnOp {
 #[derive(Debug, Clone, PartialEq)]
 pub struct ExprBinary {
     /// The left-hand side of the operation: `a`.
-    pub lhs: Spanned<Box<Expr>>,
+    pub lhs: Box<Spanned<Expr>>,
     /// The operator: `+`.
     pub op: Spanned<BinOp>,
     /// The right-hand side of the operation: `b`.
-    pub rhs: Spanned<Box<Expr>>,
+    pub rhs: Box<Spanned<Expr>>,
 }
 
 /// A binary operator.
@@ -66,3 +69,51 @@ pub enum BinOp {
     /// The division operator: `/`.
     Div,
 }
+
+/// A literal.
+#[derive(Debug, Clone, PartialEq)]
+pub enum Lit {
+    /// A identifier literal: `left`.
+    Ident(Ident),
+    /// A boolean literal: `true`, `false`.
+    Bool(bool),
+    /// An integer literal: `120`.
+    Int(i64),
+    /// A floating-point literal: `1.2`, `10e-4`.
+    Float(f64),
+    /// A length literal: `12pt`, `3cm`.
+    Length(f64, Unit),
+    /// A percent literal: `50%`.
+    ///
+    /// _Note_: `50%` is stored as `50.0` here, but as `0.5` in the
+    /// corresponding [value](crate::geom::Relative).
+    Percent(f64),
+    /// A color literal: `#ffccee`.
+    Color(RgbaColor),
+    /// A string literal: `"hello!"`.
+    Str(String),
+    /// A dictionary literal: `(false, 12cm, greeting: "hi")`.
+    Dict(LitDict),
+    /// A content literal: `{*Hello* there!}`.
+    Content(SynTree),
+}
+
+/// A dictionary literal: `(false, 12cm, greeting: "hi")`.
+#[derive(Debug, Default, Clone, PartialEq)]
+pub struct LitDict(pub Vec<LitDictEntry>);
+
+/// An entry in a dictionary literal: `false` or `greeting: "hi"`.
+#[derive(Debug, Clone, PartialEq)]
+pub struct LitDictEntry {
+    /// The key of the entry if there was one: `greeting`.
+    pub key: Option<Spanned<DictKey>>,
+    /// The value of the entry: `"hi"`.
+    pub expr: Spanned<Expr>,
+}
+
+impl LitDict {
+    /// Create an empty dict literal.
+    pub fn new() -> Self {
+        Self::default()
+    }
+}
diff --git a/src/syntax/lit.rs b/src/syntax/lit.rs
deleted file mode 100644
index 84d5c6f4..00000000
--- a/src/syntax/lit.rs
+++ /dev/null
@@ -1,54 +0,0 @@
-//! Literals.
-
-use super::*;
-use crate::color::RgbaColor;
-use crate::eval::DictKey;
-use crate::geom::Unit;
-
-/// A literal.
-#[derive(Debug, Clone, PartialEq)]
-pub enum Lit {
-    /// A identifier literal: `left`.
-    Ident(Ident),
-    /// A boolean literal: `true`, `false`.
-    Bool(bool),
-    /// An integer literal: `120`.
-    Int(i64),
-    /// A floating-point literal: `1.2`, `10e-4`.
-    Float(f64),
-    /// A length literal: `12pt`, `3cm`.
-    Length(f64, Unit),
-    /// A percent literal: `50%`.
-    ///
-    /// _Note_: `50%` is stored as `50.0` here, but as `0.5` in the
-    /// corresponding [value](crate::geom::Relative).
-    Percent(f64),
-    /// A color literal: `#ffccee`.
-    Color(RgbaColor),
-    /// A string literal: `"hello!"`.
-    Str(String),
-    /// A dictionary literal: `(false, 12cm, greeting: "hi")`.
-    Dict(LitDict),
-    /// A content literal: `{*Hello* there!}`.
-    Content(SynTree),
-}
-
-/// A dictionary literal: `(false, 12cm, greeting: "hi")`.
-#[derive(Debug, Default, Clone, PartialEq)]
-pub struct LitDict(pub Vec<LitDictEntry>);
-
-/// An entry in a dictionary literal: `false` or `greeting: "hi"`.
-#[derive(Debug, Clone, PartialEq)]
-pub struct LitDictEntry {
-    /// The key of the entry if there was one: `greeting`.
-    pub key: Option<Spanned<DictKey>>,
-    /// The value of the entry: `"hi"`.
-    pub expr: Spanned<Expr>,
-}
-
-impl LitDict {
-    /// Create an empty dict literal.
-    pub fn new() -> Self {
-        Self::default()
-    }
-}
diff --git a/src/syntax/mod.rs b/src/syntax/mod.rs
index 81702201..970cd283 100644
--- a/src/syntax/mod.rs
+++ b/src/syntax/mod.rs
@@ -2,14 +2,12 @@
 
 mod expr;
 mod ident;
-mod lit;
 mod node;
 mod span;
 mod token;
 
 pub use expr::*;
 pub use ident::*;
-pub use lit::*;
 pub use node::*;
 pub use span::*;
 pub use token::*;