rebel-lang: typing: add support for typechecking body statements

2 files changed, 20 insertions, 28 deletions

diff --git a/crates/rebel-lang/examples/repl.rs b/crates/rebel-lang/examples/repl.rs
index 914f318..db82ba6 100644
--- a/crates/rebel-lang/examples/repl.rs
+++ b/crates/rebel-lang/examples/repl.rs
@@ -85,34 +85,13 @@ fn main() {
 			}
 		};
 
-		match stmt.validate() {
-			Ok(()) => (),
-			Err(err) => {
-				println!("Validation error: {err:?}");
-				continue;
-			}
-		};
-
-		match &stmt {
-			rebel_parse::ast::BodyStmt::Assign { dest: _, expr } => {
-				match Type::ast_expr_type(&ctx, expr) {
-					Ok(_) => (),
-					Err(err) => {
-						println!("Type error: {err:?}");
-						continue;
-					}
-				};
-			}
-			rebel_parse::ast::BodyStmt::Expr { expr } => {
-				match Type::ast_expr_type(&ctx, expr) {
-					Ok(_) => (),
-					Err(err) => {
-						println!("Type error: {err:?}");
-						continue;
-					}
-				};
-			}
-			rebel_parse::ast::BodyStmt::Empty => {}
+		if let Err(err) = stmt.validate() {
+			println!("Validation error: {err:?}");
+			continue;
+		}
+		if let Err(err) = Type::ast_stmt_type(&ctx, &stmt) {
+			println!("Type error: {err:?}");
+			continue;
 		}
 
 		let value = match ctx.run(&stmt) {
diff --git a/crates/rebel-lang/src/typing.rs b/crates/rebel-lang/src/typing.rs
index 59c161b..5309e76 100644
--- a/crates/rebel-lang/src/typing.rs
+++ b/crates/rebel-lang/src/typing.rs
@@ -78,6 +78,19 @@ impl Type {
 		})
 	}
 
+	pub fn ast_stmt_type(ctx: &Context, expr: &ast::BodyStmt<'_>) -> Result<Type> {
+		match expr {
+			ast::BodyStmt::Assign { dest: _, expr } => {
+				// TODO: Assignability, dest type
+				let dest_type = Type::Free;
+				let expr_type = Self::ast_expr_type(ctx, expr)?;
+				dest_type.unify(expr_type, Coerce::Assign)
+			}
+			ast::BodyStmt::Expr { expr } => Self::ast_expr_type(ctx, expr),
+			ast::BodyStmt::Empty => Ok(Type::Unit),
+		}
+	}
+
 	pub fn ast_expr_type(ctx: &Context, expr: &ast::Expr<'_>) -> Result<Type> {
 		use ast::Expr::*;