harec

commit c7f7d297f83c885d47d0e0cad1b4579b7933a732
parent 5101702a6464961b16644b5d2a66359df4e5d418
Author: Drew DeVault <sir@cmpwn.com>
Date:   Mon, 21 Dec 2020 14:34:33 -0500

parse: simple access expressions

Diffstat:
M
include/ast.h
 | 
9
+++++++--
M
src/parse.c
 | 
53
+++++++++++++++++++++++++++++++++++++++++++++++++----

2 files changed, 56 insertions(+), 6 deletions(-)
diff --git a/include/ast.h b/include/ast.h
@@ -84,7 +84,11 @@ struct ast_type {
 	};
 };
 
-struct ast_constant_expression {
+struct ast_expression_access {
+	struct identifier ident;
+};
+
+struct ast_expression_constant {
 	enum type_storage storage;
 	union {
 		intmax_t ival;
@@ -109,7 +113,8 @@ struct ast_return_expression {
 struct ast_expression {
 	enum expr_type type;
 	union {
-		struct ast_constant_expression constant;
+		struct ast_expression_access access;
+		struct ast_expression_constant constant;
 		struct ast_expression_list list;
 		struct ast_return_expression _return;
 	};
diff --git a/src/parse.c b/src/parse.c
@@ -335,12 +335,21 @@ parse_type(struct parser *par, struct ast_type *type)
 }
 
 static void
-parse_simple_expression(struct parser *par, struct ast_expression *exp)
+parse_access(struct parser *par, struct ast_expression *exp)
+{
+	trenter(TR_PARSE, "access");
+	exp->type = EXPR_ACCESS;
+	parse_identifier(par, &exp->access.ident);
+	trleave(TR_PARSE, NULL);
+}
+
+static void
+parse_constant(struct parser *par, struct ast_expression *exp)
 {
-	trenter(TR_PARSE, "simple-expression");
-	struct token tok = {0};
-	want(par, T_LITERAL, &tok); // TODO: other simple expressions
 	trenter(TR_PARSE, "constant");
+
+	struct token tok = {0};
+	want(par, T_LITERAL, &tok);
 	exp->type = EXPR_CONSTANT;
 	exp->constant.storage = tok.storage;
 	switch (tok.storage) {
@@ -372,6 +381,42 @@ parse_simple_expression(struct parser *par, struct ast_expression *exp)
 		assert(0); // TODO
 	}
 	trleave(TR_PARSE, "%s", token_str(&tok));
+
+	trleave(TR_PARSE, NULL);
+}
+
+static void
+parse_simple_expression(struct parser *par, struct ast_expression *exp)
+{
+	trenter(TR_PARSE, "simple-expression");
+
+	// TODO: This will need to be refactored once we finish the grammar
+	// connecting postfix-expression to logical-or-expression
+	struct token tok = {0};
+	lex(par->lex, &tok);
+	switch (tok.token) {
+	// plain-expression
+	case T_NAME:
+		unlex(par->lex, &tok);
+		parse_access(par, exp);
+		break;
+	case T_LITERAL:
+		unlex(par->lex, &tok);
+		parse_constant(par, exp);
+		break;
+	case T_LBRACKET:
+		assert(0); // TODO: array/slice literal
+	case T_LBRACE:
+		assert(0); // TODO: array/slice literal
+	// nested-expression
+	case T_LPAREN:
+		assert(0); // TODO: nested-expression
+	// syntax error
+	default:
+		synassert(false, &tok, T_LITERAL, T_NAME, T_EOF);
+		break;
+	}
+
 	trleave(TR_PARSE, NULL);
 }