Flatten ast module back into syntax module 🌪

1 files changed, 68 insertions, 0 deletions

diff --git a/src/syntax/expr.rs b/src/syntax/expr.rs
new file mode 100644
index 00000000..09729f52
--- /dev/null
+++ b/src/syntax/expr.rs
@@ -0,0 +1,68 @@
+//! Expressions.
+
+use super::*;
+
+/// An expression.
+#[derive(Debug, Clone, PartialEq)]
+pub enum Expr {
+    /// A literal: `true`, `1cm`, `"hi"`, `{_Hey!_}`.
+    Lit(Lit),
+    /// An invocation of a function: `[foo: ...]`, `foo(...)`.
+    Call(ExprCall),
+    /// A unary operation: `-x`.
+    Unary(ExprUnary),
+    /// A binary operation: `a + b`, `a / b`.
+    Binary(ExprBinary),
+}
+
+/// An invocation of a function: `[foo: ...]`, `foo(...)`.
+#[derive(Debug, Clone, PartialEq)]
+pub struct ExprCall {
+    /// The name of the function.
+    pub name: Spanned<Ident>,
+    /// The arguments to the function.
+    ///
+    /// In case of a bracketed invocation with a body, the body is _not_
+    /// included in the span for the sake of clearer error messages.
+    pub args: Spanned<LitDict>,
+}
+
+/// A unary operation: `-x`.
+#[derive(Debug, Clone, PartialEq)]
+pub struct ExprUnary {
+    /// The operator: `-`.
+    pub op: Spanned<UnOp>,
+    /// The expression to operator on: `x`.
+    pub expr: Spanned<Box<Expr>>,
+}
+
+/// A unary operator.
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub enum UnOp {
+    /// The negation operator: `-`.
+    Neg,
+}
+
+/// A binary operation: `a + b`, `a / b`.
+#[derive(Debug, Clone, PartialEq)]
+pub struct ExprBinary {
+    /// The left-hand side of the operation: `a`.
+    pub lhs: Spanned<Box<Expr>>,
+    /// The operator: `+`.
+    pub op: Spanned<BinOp>,
+    /// The right-hand side of the operation: `b`.
+    pub rhs: Spanned<Box<Expr>>,
+}
+
+/// A binary operator.
+#[derive(Debug, Copy, Clone, Eq, PartialEq)]
+pub enum BinOp {
+    /// The addition operator: `+`.
+    Add,
+    /// The subtraction operator: `-`.
+    Sub,
+    /// The multiplication operator: `*`.
+    Mul,
+    /// The division operator: `/`.
+    Div,
+}