hare

commit 7f3283f2e743611463be7f1fe7b1bf0d92a78f24
parent 07c4c8efb39a29d5accfdd79a0581930e697104e
Author: Joe Finney <me@spxtr.net>
Date:   Sun, 10 Mar 2024 14:23:13 +0000

Update hare::parse for optional function params.

Signed-off-by: Joe Finney <me@spxtr.net>

Diffstat:
M
hare/ast/type.ha
 | 
1
+
M
hare/parse/+test/types.ha
 | 
2
+-
M
hare/parse/type.ha
 | 
8
++++++++
M
hare/unparse/decl.ha
 | 
13
++++++++++++-
M
hare/unparse/type.ha
 | 
12
++++++++++++

5 files changed, 34 insertions(+), 2 deletions(-)
diff --git a/hare/ast/type.ha b/hare/ast/type.ha
@@ -42,6 +42,7 @@ export type func_param = struct {
 	loc: lex::location,
 	name: str,
 	_type: *_type,
+	default_value: (void | expr),
 };
 
 // fn(foo: int, baz: int...) int
diff --git a/hare/parse/+test/types.ha b/hare/parse/+test/types.ha
@@ -129,7 +129,7 @@ export type foo = fn(
 	long_type_name,
 	blablablabla,
 	multiple_lines,
-	and_stuff,
+	and_stuff = 4,
 ) void;
 
 export type foo = fn(
diff --git a/hare/parse/type.ha b/hare/parse/type.ha
@@ -28,6 +28,7 @@ fn prototype(lexer: *lex::lexer) (ast::func_type | error) = {
 				loc = loc,
 				name = "",
 				_type = alloc(name_or_type),
+				default_value = void,
 			});
 		case lex::token =>
 			// Bit of a hack because we can't unlex twice.
@@ -39,8 +40,15 @@ fn prototype(lexer: *lex::lexer) (ast::func_type | error) = {
 				loc = loc,
 				name = ns[0],
 				_type = alloc(_type(lexer)?),
+				default_value = void,
 			});
 		};
+		match (try(lexer, ltok::EQUAL)?) {
+		case void =>
+			yield void;
+		case lex::token =>
+			params[len(params) - 1].default_value = expr(lexer)?;
+		};
 		match (try(lexer, ltok::ELLIPSIS)?) {
 		case lex::token =>
 			variadism = ast::variadism::HARE;
diff --git a/hare/unparse/decl.ha b/hare/unparse/decl.ha
@@ -181,6 +181,7 @@ fn decl_test(d: *ast::decl, expected: str) bool = {
 	decl(&buf, &syn_nowrap, d)!;
 	let s = memio::string(&buf)!;
 	defer free(s);
+	fmt::println(s)!;
 	return s == expected;
 };
 
@@ -208,11 +209,13 @@ fn decl_test(d: *ast::decl, expected: str) bool = {
 					loc = loc,
 					name = "foo",
 					_type = &type_int,
+					default_value = void,
 				},
 				ast::func_param {
 					loc = loc,
 					name = "bar",
 					_type = &type_int,
+					default_value = void,
 				},
 			],
 		},
@@ -297,6 +300,14 @@ fn decl_test(d: *ast::decl, expected: str) bool = {
 				loc = loc,
 				name = "",
 				_type = &type_int,
+				default_value = ast::expr {
+					expr = ast::number_literal {
+						value = 4u64,
+						sign = false,
+						suff = lex::ltok::LIT_ICONST,
+					},
+					...
+				},
 			},
 		],
 	};
@@ -307,5 +318,5 @@ fn decl_test(d: *ast::decl, expected: str) bool = {
 		body = &expr_void,
 		attrs = 0,
 	};
-	assert(decl_test(&d, "fn foo(int) int = void;"));
+	assert(decl_test(&d, "fn foo(int = 4) int = void;"));
 };
diff --git a/hare/unparse/type.ha b/hare/unparse/type.ha
@@ -78,6 +78,15 @@ fn prototype(
 			n += space(ctx)?;
 		};
 		n += __type(ctx, syn, param._type)?;
+		match (param.default_value) {
+		case void =>
+			yield;
+		case let e: ast::expr =>
+			n += space(ctx)?;
+			n += syn(ctx, "=", synkind::PUNCTUATION)?;
+			n += space(ctx)?;
+			n += _expr(ctx, syn, &e)?;
+		};
 		if (i + 1 < len(t.params) || t.variadism == variadism::C) {
 			n += syn(ctx, ",", synkind::PUNCTUATION)?;
 			n += space(ctx)?;
@@ -396,6 +405,7 @@ fn type_test(t: *ast::_type, expected: str) void = {
 				loc = loc,
 				name = "",
 				_type = &type_int,
+				default_value = void,
 			},
 		],
 	};
@@ -408,11 +418,13 @@ fn type_test(t: *ast::_type, expected: str) void = {
 				loc = loc,
 				name = "foo",
 				_type = &type_int,
+				default_value = void,
 			},
 			ast::func_param {
 				loc = loc,
 				name = "bar",
 				_type = &type_int,
+				default_value = void,
 			},
 		],
 	};