hare

commit 21aa89bf1a4b9798995d96322d4abccd52a85bb0
parent c7a4513af88ba92af8cbf96cf178b332e6b288ba
Author: Drew DeVault <sir@cmpwn.com>
Date:   Sun, 18 Apr 2021 13:25:18 -0400

hare::parse: implement append expressions

Diffstat:
M
hare/ast/expr.ha
 | 
4
++--
M
hare/parse/+test/expr.ha
 | 
3
+++
M
hare/parse/expr.ha
 | 
51
++++++++++++++++++++++++++++++++++++++++++++++-----
M
hare/unparse/expr.ha
 | 
22
+++++++++++++++++++++-

4 files changed, 72 insertions(+), 8 deletions(-)
diff --git a/hare/ast/expr.ha b/hare/ast/expr.ha
@@ -32,7 +32,7 @@ export type alloc_expr = struct {
 
 // append(foo, bar, (more), baz...)
 export type append_expr = struct {
-	expr: *expr,
+	object: *expr,
 	variadic: nullable *expr,
 	values: []*expr,
 };
@@ -284,7 +284,7 @@ export fn expr_free(e: (expr | nullable *expr)) void = match (e) {
 			expr_free(a.capacity);
 		},
 		a: append_expr => {
-			expr_free(a.expr);
+			expr_free(a.object);
 			match (a.variadic) {
 				null => void,
 				v: *expr => expr_free(v),
diff --git a/hare/parse/+test/expr.ha b/hare/parse/+test/expr.ha
@@ -35,6 +35,9 @@
 	roundtrip("export fn main() void = {
 	alloc(1234);
 	alloc(4321, 1234);
+	append(x, 10);
+	append(x, 10, 20, 30);
+	append(x, y, z, q...);
 };
 ");
 };
diff --git a/hare/parse/expr.ha b/hare/parse/expr.ha
@@ -95,6 +95,47 @@ fn alloc_expr(lexer: *lex::lexer) (ast::expr | error) = {
 	};
 };
 
+fn append_expr(lexer: *lex::lexer) (ast::expr | error) = {
+	want(lexer, ltok::APPEND)?;
+	want(lexer, ltok::LPAREN)?;
+
+	const object =
+		if (try(lexer, ltok::TIMES)? is lex::token) unarithm(lexer)?
+		else objsel(lexer)?;
+	want(lexer, ltok::COMMA)?;
+
+	let variadic: nullable *ast::expr = null;
+	let values: []*ast::expr = [];
+	for (true) {
+		if (try(lexer, ltok::RPAREN)? is lex::token) break;
+
+		const expr = alloc(expression(lexer)?);
+		switch (want(lexer, ltok::COMMA, ltok::ELLIPSIS, ltok::RPAREN)?.0) {
+			ltok::COMMA => append(values, expr),
+			ltok::ELLIPSIS => {
+				variadic = expr;
+				try(lexer, ltok::COMMA)?;
+				want(lexer, ltok::RPAREN)?;
+				break;
+			},
+			ltok::RPAREN => {
+				append(values, expr);
+				break;
+			},
+			* => abort(),
+		};
+	};
+
+	synassert(mkloc(lexer), variadic != null || len(values) != 0,
+		"Expected values to append")?;
+
+	return ast::append_expr {
+		object = alloc(object),
+		variadic = variadic,
+		values = values,
+	};
+};
+
 fn binarithm(
 	lexer: *lex::lexer,
 	lvalue: (ast::expr | void),
@@ -174,10 +215,10 @@ fn builtin(lexer: *lex::lexer) (ast::expr | error) = {
 	};
 	return switch (tok.0) {
 		ltok::ALLOC => alloc_expr(lexer)?,
-		ltok::APPEND => abort(),
-		ltok::DELETE => abort(),
-		ltok::FREE => abort(),
-		ltok::ASSERT => abort(),
+		ltok::APPEND => append_expr(lexer)?,
+		ltok::DELETE => abort(), // TODO
+		ltok::FREE => abort(), // TODO
+		ltok::ASSERT => abort(), // TODO
 		ltok::STATIC => {
 			want(lexer, ltok::STATIC)?;
 			let tok = match (peek(lexer, ltok::LET, ltok::CONST,
@@ -193,7 +234,7 @@ fn builtin(lexer: *lex::lexer) (ast::expr | error) = {
 				* => abort(),
 			};
 		},
-		ltok::SIZE, ltok::LEN, ltok::OFFSET => abort(),
+		ltok::SIZE, ltok::LEN, ltok::OFFSET => abort(), // TODO
 		ltok::DEFER => {
 			want(lexer, ltok::DEFER)?;
 			alloc(expression(lexer)?): ast::defer_expr;
diff --git a/hare/unparse/expr.ha b/hare/unparse/expr.ha
@@ -46,7 +46,27 @@ export fn expr(
 			z += fmt::fprint(out, ")")?;
 			z;
 		},
-		e: ast::append_expr => abort(),
+		e: ast::append_expr => {
+			let z = fmt::fprint(out, "append(")?;
+			z += expr(out, indent, *e.object)?;
+			z += fmt::fprint(out, ", ")?;
+			for (let i = 0z; i < len(e.values); i += 1) {
+				let val = e.values[i];
+				z += expr(out, indent, *val)?;
+				if (i + 1 < len(e.values)) {
+					z += fmt::fprint(out, ", ")?;
+				};
+			};
+			match (e.variadic) {
+				null => void,
+				e: *ast::expr => {
+					z += fmt::fprint(out, ", ")?;
+					z += expr(out, indent, *e)?;
+					z += fmt::fprint(out, "...")?;
+				},
+			};
+			z + fmt::fprint(out, ")")?;
+		},
 		e: ast::assert_expr => abort(),
 		e: ast::assign_expr => {
 			let z = 0z;