rebel-parse, rebel-lang: add support for map literals

4 files changed, 46 insertions, 0 deletions

diff --git a/crates/rebel-lang/src/typing.rs b/crates/rebel-lang/src/typing.rs
index ef46201..bd8ba10 100644
--- a/crates/rebel-lang/src/typing.rs
+++ b/crates/rebel-lang/src/typing.rs
@@ -511,6 +511,18 @@ impl<'scope> Context<'scope> {
 					acc.unify(self.type_expr(elem)?, Coerce::Common)
 				})?,
 			)),
+			Literal::Map(entries) => {
+				let (key, value) = entries.iter().try_fold(
+					(Type::Free, Type::Free),
+					|(acc_key, acc_value), expr::MapEntry { key, value }| {
+						Ok((
+							acc_key.unify(self.type_expr(key)?, Coerce::Common)?,
+							acc_value.unify(self.type_expr(value)?, Coerce::Common)?,
+						))
+					},
+				)?;
+				Type::Map(key.try_into()?, Box::new(value))
+			}
 			Literal::Struct(entries) => Struct(
 				entries
 					.iter()
diff --git a/crates/rebel-lang/src/value.rs b/crates/rebel-lang/src/value.rs
index bd040aa..ad78ac7 100644
--- a/crates/rebel-lang/src/value.rs
+++ b/crates/rebel-lang/src/value.rs
@@ -431,6 +431,18 @@ impl<'scope> Context<'scope> {
 					.map(|elem| self.eval_expr(elem))
 					.collect::<Result<_>>()?,
 			),
+			Literal::Map(entries) => {
+				let map: FxHashMap<_, _> = entries
+					.iter()
+					.map(|expr::MapEntry { key, value }| {
+						Ok((self.eval_expr(key)?.try_into()?, self.eval_expr(value)?))
+					})
+					.collect::<Result<_>>()?;
+				if map.len() != entries.len() {
+					return Err(Error::eval("duplicate map key"));
+				}
+				Map(map)
+			}
 			Literal::Struct(entries) => Struct(
 				entries
 					.iter()
diff --git a/crates/rebel-parse/src/ast/expr.rs b/crates/rebel-parse/src/ast/expr.rs
index 341b8ad..0a47cb2 100644
--- a/crates/rebel-parse/src/ast/expr.rs
+++ b/crates/rebel-parse/src/ast/expr.rs
@@ -193,6 +193,7 @@ pub enum Literal<'a> {
 	},
 	Tuple(Vec<Expr<'a>>),
 	Array(Vec<Expr<'a>>),
+	Map(Vec<MapEntry<'a>>),
 	Struct(Vec<StructField<'a>>),
 }
 
@@ -224,6 +225,13 @@ impl<'a> Literal<'a> {
 				}
 				Ok(())
 			}
+			Literal::Map(entries) => {
+				for MapEntry { key, value } in entries {
+					key.validate()?;
+					value.validate()?;
+				}
+				Ok(())
+			}
 			Literal::Struct(entries) => {
 				let mut fields = FxHashSet::default();
 				for StructField { name, value } in entries {
@@ -262,6 +270,12 @@ impl<'a> TryFrom<&token::StrPiece<'a>> for StrPiece<'a> {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
+pub struct MapEntry<'a> {
+	pub key: Expr<'a>,
+	pub value: Expr<'a>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct StructField<'a> {
 	pub name: &'a str,
 	pub value: Expr<'a>,
diff --git a/crates/rebel-parse/src/grammar/recipe.rs b/crates/rebel-parse/src/grammar/recipe.rs
index 1ada80c..8181ee2 100644
--- a/crates/rebel-parse/src/grammar/recipe.rs
+++ b/crates/rebel-parse/src/grammar/recipe.rs
@@ -178,10 +178,18 @@ peg::parser! {
 			/ p('[') elements:delimited(<expr()>, <p(',')>) p(']') {
 				expr::Literal::Array(elements)
 			}
+			/ [Token::Keyword(Keyword::Map)] p('{') entries:delimited(<map_entry()>, <p(',')>) p('}') {
+				expr::Literal::Map(entries)
+			}
 			/ [Token::Keyword(Keyword::Struct)] p('{') entries:delimited(<struct_field()>, <p(',')>) p('}') {
 				expr::Literal::Struct(entries)
 			}
 
+		rule map_entry() -> expr::MapEntry<'a>
+			= key:expr() p2('=', '>') value:expr() {
+				expr::MapEntry { key, value }
+			}
+
 		rule struct_field() -> expr::StructField<'a>
 			= field:field() p('=') value:expr() {
 				expr::StructField { name: field.name, value }