hare

commit 73647c00b26774d960e65fee9b502440904d4aed
parent abf25291435bcf240a753be2ee0ed987c4877329
Author: Eyal Sawady <ecs@d2evs.net>
Date:   Wed, 28 Apr 2021 15:25:26 -0400

hare::parse: update for reverted match syntax

Signed-off-by: Eyal Sawady <ecs@d2evs.net>

Diffstat:
M
hare/parse/+test/expr.ha
 | 
7
+++++--
M
hare/parse/expr.ha
 | 
24
++++++++++--------------
M
hare/parse/parse.ha
 | 
41
+++++++++++++++++++++++++++++++++++++++++
M
hare/unparse/expr.ha
 | 
6
------

4 files changed, 56 insertions(+), 22 deletions(-)
diff --git a/hare/parse/+test/expr.ha b/hare/parse/+test/expr.ha
@@ -216,14 +216,17 @@
 	roundtrip("export fn main() void = {
 	match (x) {
 		i: size => y,
-		_: str => {
+		str => {
 			z;
 		},
+		foo => bar,
+		foo: int => bar,
+		foo::bar => baz,
 		null => void,
 	};
 	match (x) {
 		s: matchdata => y,
-		_: str => {
+		str => {
 			z;
 		},
 		* => q,
diff --git a/hare/parse/expr.ha b/hare/parse/expr.ha
@@ -821,22 +821,18 @@ fn switch_expr(lexer: *lex::lexer) (ast::expr | error) = {
 };
 
 fn match_case(lexer: *lex::lexer) (ast::match_case | error) = {
-	let tok = want(lexer, ltok::NAME, ltok::UNDERSCORE, ltok::NULL)?;
+	let tok = peek(lexer)? as lex::token;
+	let loc = tok.2;
 	let nt = switch (tok.0) {
-		ltok::NAME => {
-			let name = tok.1 as str;
-			want(lexer, ltok::COLON)?;
-			(name, _type(lexer)?);
-		},
-		ltok::UNDERSCORE => {
-			want(lexer, ltok::COLON)?;
-			("", _type(lexer)?);
+		ltok::NULL => {
+			want(lexer, ltok::NULL)?;
+			("", ast::_type {
+				loc = loc,
+				flags = 0,
+				_type = ast::builtin_type::NULL,
+			});
 		},
-		ltok::NULL => ("", ast::_type {
-			loc = tok.2,
-			flags = 0,
-			_type = ast::builtin_type::NULL,
-		}),
+		* => nametype(lexer)?,
 	};
 	want(lexer, ltok::CASE)?;
 	let expr = expression(lexer)?;
diff --git a/hare/parse/parse.ha b/hare/parse/parse.ha
@@ -1,5 +1,6 @@
 use fmt;
 use hare::ast;
+use hare::lex::{ltok};
 use hare::lex;
 use io;
 use strio;
@@ -92,3 +93,43 @@ fn synassert(loc: lex::location, cond: bool, msg: str) (void | error) = {
 		return syntaxerr(loc, msg);
 	};
 };
+
+fn nametype(lexer: *lex::lexer) ((str, ast::_type) | error) = {
+	let tok = peek(lexer)? as lex::token;
+	let loc = tok.2;
+	return switch (tok.0) {
+		ltok::NAME => {
+			let name = tok.1 as str;
+			want(lexer, ltok::NAME)?;
+			tok = peek(lexer)? as lex::token;
+			switch (tok.0) {
+				ltok::COLON => {
+					want(lexer, ltok::COLON)?;
+					(name, _type(lexer)?);
+				},
+				ltok::DOUBLE_COLON => {
+					want(lexer, ltok::DOUBLE_COLON)?;
+					let id = ident(lexer)?;
+					insert(id[0], name);
+					("", ast::_type {
+						loc = loc,
+						flags = 0,
+						_type = ast::alias_type {
+							unwrap = false,
+							ident = id,
+						},
+					});
+				},
+				* => ("", ast::_type {
+					loc = loc,
+					flags = 0,
+					_type = ast::alias_type {
+						unwrap = false,
+						ident = alloc([name]),
+					},
+				}),
+			};
+		},
+		* => ("", _type(lexer)?),
+	};
+};
diff --git a/hare/unparse/expr.ha b/hare/unparse/expr.ha
@@ -458,14 +458,8 @@ fn match_expr(
 	for (let i = 0z; i < len(e.cases); i += 1) {
 		z += newline(out, indent)?;
 		const case = e.cases[i];
-		const is_null = match (case._type._type) {
-			b: ast::builtin_type => b == ast::builtin_type::NULL,
-			* => false,
-		};
 		if (len(case.name) > 0) {
 			z += fmt::fprintf(out, "{}: ", case.name)?;
-		} else if (!is_null) {
-			z += fmt::fprintf(out, "_: ")?;
 		};
 		z += _type(out, indent, *case._type)?;
 		z += fmt::fprint(out, " => ")?;