parse function

2 files changed, 78 insertions, 14 deletions

diff --git a/src/main.c b/src/main.c
index 8c75915..0bfa197 100644
--- a/src/main.c
+++ b/src/main.c
@@ -57,7 +57,7 @@ static Token *
 skip(Token *tok, char *s)
 {
 	if (!equal(tok, s))
-		error("expected '%s'", s);
+		error("expected '%s'; got '%.*s'", s, tok->len, tok->loc);
 	return tok->next;
 }
 
@@ -86,7 +86,7 @@ is_punct(const char *p)
 	if (strchr("=!<>", p[0]) != NULL && p[1] == '=')
 		return 2;
 
-	return (strchr("+-/*()<>;", p[0]) != NULL);
+	return (strchr("+-/*()<>,;{}", p[0]) != NULL);
 }
 
 static Token *
@@ -111,7 +111,7 @@ tokenize(char *p)
 
 		if (*p == '\'' && p[1] != '\0' && p[2] == '\'') {
 			cur = cur->next = new_token(TOK_NUM, p, p + 3);
-			cur->val = (unsigned char)*p;
+			cur->val = (unsigned char)p[1];
 			p += 3;
 			continue;
 		}
@@ -125,7 +125,7 @@ tokenize(char *p)
 
 		if (isalpha(*p)) {
 			char *q = p;
-			while (isalnum(*p))
+			while (isalnum(*p) || *p == '_')
 				p += 1;
 			cur = cur->next = new_token(TOK_WORD, q, p);
 			continue;
@@ -149,7 +149,8 @@ typedef enum {
 	NOD_LE,  // <=
 	NOD_NUM, // integer
 	NOD_EXPR_STMT,
-	NOD_FUN_STMT,
+	NOD_FUN,
+	NOD_WORD,
 } NodeType;
 
 typedef struct Node Node;
@@ -159,6 +160,8 @@ struct Node {
 	Node *rhs;
 	Node *next;
 	int val;
+	char *loc;
+	int len;
 };
 
 static Node *
@@ -172,6 +175,17 @@ new_node(NodeType type)
 }
 
 static Node *
+new_word(Token *tok)
+{
+	expect(tok, TOK_WORD);
+
+	Node *const node = new_node(NOD_WORD);
+	node->loc = tok->loc;
+	node->len = tok->len;
+	return node;
+}
+
+static Node *
 new_binary(NodeType type, Node *lhs, Node *rhs)
 {
 	Node *const node = new_node(type);
@@ -194,6 +208,8 @@ new_num(int val)
 	return node;
 }
 
+static Node *stmt(Token **rest, Token *tok);
+static Node *function(Token **rest, Token *tok);
 static Node *expr(Token **rest, Token *tok);
 static Node *expr_stmt(Token **rest, Token *tok);
 static Node *equality(Token **rest, Token *tok);
@@ -202,8 +218,41 @@ static Node *add(Token **rest, Token *tok);
 static Node *mul(Token **rest, Token *tok);
 static Node *primary(Token **rest, Token *tok);
 
-static Node
-*expr(Token **rest, Token *tok)
+static Node *
+function(Token **rest, Token *tok)
+{
+	Node *const node = new_node(NOD_FUN);
+
+	tok = skip(tok, "fn");
+
+	node->lhs = new_word(tok);
+	tok = skip(tok->next, "(");
+
+	Node head = {0};
+	Node *cur = &head;
+	while (tok->type == TOK_WORD) {
+		cur = cur->next = new_word(tok);
+		tok = tok->next;
+		if (equal(tok, ","))
+			tok = tok->next;
+	}
+	node->lhs->next = cur;
+	tok = skip(tok, ")");
+	tok = skip(tok, "{");
+
+	cur = &head;
+	while (tok->type != TOK_EOF && !equal(tok, "}"))
+		cur = cur->next = stmt(&tok, tok);
+	tok = skip(tok, "}");
+
+	node->rhs = head.next;
+
+	*rest = tok;
+	return node;
+}
+
+static Node *
+expr(Token **rest, Token *tok)
 {
 	return equality(rest, tok);
 }
@@ -387,8 +436,11 @@ gen_expr(Node *node)
 }
 
 static void
-codegen(Node *node)
+gen_function(Node *node)
 {
+	printf("@_fn_%.*s\n", node->lhs->len, node->lhs->loc);
+
+	node = node->rhs;
 	while (node != NULL) {
 		gen_expr(node->lhs);
 		while (depth) {
@@ -397,6 +449,17 @@ codegen(Node *node)
 		}
 		node = node->next;
 	}
+
+	printf("\tLIT 0000 ( default return )\n\tRET\n");
+}
+
+static void
+codegen(Node *node)
+{
+	while (node != NULL) {
+		gen_function(node);
+		node = node->next;
+	}
 }
 
 // program = stmt*
@@ -406,7 +469,7 @@ parse(Token *tok)
 	Node head = {0};
 	Node *cur = &head;
 	while (tok->type != TOK_EOF)
-		cur = cur->next = stmt(&tok, tok);
+		cur = cur->next = function(&tok, tok);
 	return head.next;
 }
 
@@ -420,9 +483,8 @@ main(int argc, char **argv)
 
 	Node *node = parse(tok);
 
-	printf("\tJMP ,main\n");
+	printf("\tJMP ,_fn_main ( entry point )\n");
 	codegen(node);
-	printf("\tRET\n");
 
 	assert(depth == 0);
 	return 0;
diff --git a/testing.sh b/testing.sh
index 7abae1d..467d899 100755
--- a/testing.sh
+++ b/testing.sh
@@ -4,12 +4,14 @@ function test() {
 	CODE="$1"
 	echo "--- $CODE ---"
 	./build/golem "$CODE" >"build/tmp.orgaasm"
+	cat "build/tmp.orgaasm"
 	orgaasm "build/tmp.orgaasm" "build/tmp.rom"
 	orgaemu "build/tmp.rom"
+	echo ""
 }
 
 tup || exit 1
-test "5 + 2;"
-test "6 + 3;"
-test "'a' - 'b';"
+test "fn main(){5 + 2;}"
+test "fn main(){6 + 3;}"
+test "fn main(){'a' - 'b';}"
 rm -f build/tmp.*