Added fairly limited type inference

parser/src/ast.rs

@@ -178,8 +178,15 @@ pub struct Field {
 
 #[derive(Debug)]
 pub struct StructCtor {
-	pub r#type: Expr,
+	pub r#type: Option<Expr>,
 	pub r#values: IndexMap<Substr, NameValuePair>,
+	pub(crate) range: Range<usize>,
+}
+
+impl StructCtor {
+	pub fn range(&self) -> Range<usize> {
+		self.range.clone()
+	}
 }
 
 #[derive(Debug)]

parser/src/parser.rs

@@ -81,9 +81,18 @@ peg::parser! {
 			lhs:@ "(" __ args:(expr() ** list_separator()) __ ")" { Expr::Call { func: lhs.into(), args } }
 			value:@ "[" __ index:expr() __ "]" { Expr::Index(IndexingExpr { value, index }.into()) }
 
-			r#type:@ __ "#{" __ values:name_value_pairs() __ "}" { Expr::Struct(
+			ty:@ __ "#{" __ values:name_value_pairs() __ "}" e:position!()  { Expr::Struct(
 				StructCtor {
-					r#type, values: values.into_iter().map(|v| (v.name.0.clone(), v)).collect()
+					range: ty.range().start..e,
+					r#type: Some(ty),
+					values: values.into_iter().map(|v| (v.name.0.clone(), v)).collect(),
+				}.into()
+			) }
+			s:position!()  "#{" __ values:name_value_pairs() __ "}" e:position!() { Expr::Struct(
+				StructCtor {
+					r#type: None,
+					values: values.into_iter().map(|v| (v.name.0.clone(), v)).collect(),
+					range: s..e,
 				}.into()
 			) }
 			--