hare

commit ca7d1b9b80ce7eeb1b1ba9c39d98c7bb85f3b6c3
parent 18956d45e246e570b0bd308ee8b08658a9b930e2
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sun, 18 Apr 2021 10:25:28 -0400

hare::parse: implement defer expressions

Diffstat:
M
hare/parse/+test/expr.ha
 | 
4
++++
M
hare/parse/expr.ha
 | 
5
++++-
M
hare/unparse/expr.ha
 | 
3
++-

3 files changed, 10 insertions(+), 2 deletions(-)
diff --git a/hare/parse/+test/expr.ha b/hare/parse/+test/expr.ha
@@ -54,6 +54,10 @@
 ");
 };
 
+@test fn defer_expr() void = {
+	roundtrip("export fn main() void = defer foo();\n");
+};
+
 @test fn for_expr() void = {
 	roundtrip("export fn main() void = {
 	for (true) {
diff --git a/hare/parse/expr.ha b/hare/parse/expr.ha
@@ -123,7 +123,10 @@ fn builtin(lexer: *lex::lexer) (ast::expr | error) = {
 			};
 		},
 		ltok::SIZE, ltok::LEN, ltok::OFFSET => abort(),
-		ltok::DEFER => abort(),
+		ltok::DEFER => {
+			want(lexer, ltok::DEFER)?;
+			alloc(expression(lexer)?): ast::defer_expr;
+		},
 		* => abort(), // Invariant
 	};
 };
diff --git a/hare/unparse/expr.ha b/hare/unparse/expr.ha
@@ -126,7 +126,8 @@ export fn expr(
 			};
 			z;
 		},
-		e: ast::defer_expr => abort(),
+		e: ast::defer_expr =>
+			fmt::fprint(out, "defer ")? + expr(out, indent, *e)?,
 		e: ast::delete_expr => abort(),
 		e: ast::for_expr => for_expr(out, indent, e)?,
 		e: ast::free_expr => abort(),