add assignment statements

1 files changed, 65 insertions, 45 deletions

diff --git a/main.c b/main.c
index 05c639c..ee759dd 100644
--- a/main.c
+++ b/main.c
@@ -28,50 +28,6 @@ void unit_free(Unit *u) {
 	free(u->procs.data);
 }
 
-void node_print(Node *n) {
-	if (n->type == N_LIT) {
-		printf("\t%d [label=\"%ld\"]\n", n->id, n->val.i);
-	} else {
-		printf("\t%d [label=\"%s\", shape=record]\n", n->id, node_type_name(n->type));
-	}
-	if (n->walked) {
-		return;
-	}
-	n->walked = 1;
-	for (int i = 0; i < n->out.len; i++) {
-		if (n->out.data[i]->type == N_LIT) {
-			printf("\t%d -> %d [style=dashed]\n", n->id, n->out.data[i]->id);
-		} else {
-			printf("\t%d -> %d\n", n->id, n->out.data[i]->id);
-		}
-	}
-	for (int i = 0; i < n->out.len; i++) {
-		node_print(n->out.data[i]);
-	}
-}
-
-void proc_print(Proc *p) {
-	if (p->start) {
-		printf("\t\"%.*s\" -> %d\n", (int)p->name.n, p->name.s, p->start->id);
-		node_print(p->start);
-		if (no_opt) {
-			for (NameBinding *b = p->scope.free_bind; b; b = b->prev) {
-				uint64_t id = (uintptr_t)b->node;
-				printf("\t\t%lu [label=\"%.*s\",shape=none,fontcolor=blue]\n", id, (int)b->name.n, b->name.s);
-				printf("\t\t%lu -> %d [arrowhead=none,style=dotted,color=blue]\n", id, b->node->id);
-			}
-		}
-	}
-}
-
-void unit_print(Unit *u) {
-	puts("digraph {");
-	for (int i = 0; i < u->procs.len; i++) {
-		proc_print(&u->procs.data[i]);
-	}
-	puts("}");
-}
-
 /* parsing */
 
 Node *parse_expr(Lexer *l, Proc *p);
@@ -86,7 +42,7 @@ recurse:
 	lex_expect(l, TM_IDENT);
 	Str name = l->ident;
 	LexSpan pos = l->pos;
-	lex_expect(l, TM_EQUALS);
+	lex_expect(l, TM_EQL);
 	lex_next(l);
 	Node *rhs = parse_expr(l, p);
 	NameBinding *b = scope_bind(&p->scope, name, rhs, pos, p);
@@ -112,6 +68,17 @@ void parse_block(Lexer *l, Proc *p) {
 	lex_next(l);
 }
 
+void parse_assign(Lexer *l, Proc *p) {
+	Str name = l->ident;
+	LexSpan pos = l->pos;
+	lex_expect(l, TM_ASSIGN);
+	lex_next(l);
+	Node *e = parse_expr(l, p);
+	if (!scope_update(&p->scope, name, e, p)) {
+		lex_error_at(l, pos, LE_ERROR, S("undeclared identifier"));
+	}
+}
+
 void parse_stmt(Lexer *l, Proc *p) {
 	/* TODO */
 	(void)l;
@@ -125,6 +92,9 @@ void parse_stmt(Lexer *l, Proc *p) {
 	case TOK_LBRACE:
 		parse_block(l, p);
 		break;
+	case TOK_IDENT:
+		parse_assign(l, p);
+		break;
 	default:
 		lex_expected(l, TM_RBRACE);
 		break;
@@ -233,6 +203,8 @@ void parse_toplevel(Lexer *l, Unit *u) {
 	}
 }
 
+
+void unit_print(Unit *u);
 void parse_unit(Lexer *l) {
 	Unit u = { 0 };
 	unit_init(&u);
@@ -243,6 +215,54 @@ void parse_unit(Lexer *l) {
 	unit_free(&u);
 }
 
+/* graph output */
+
+void node_print(Node *n) {
+	if (n->type == N_LIT) {
+		printf("\t%d [label=\"%ld\"]\n", n->id, n->val.i);
+	} else {
+		printf("\t%d [label=\"%s\", shape=record]\n", n->id, node_type_name(n->type));
+	}
+	if (n->walked) {
+		return;
+	}
+	n->walked = 1;
+	for (int i = 0; i < n->out.len; i++) {
+		if (n->out.data[i]->type == N_LIT) {
+			printf("\t%d -> %d [style=dashed]\n", n->id, n->out.data[i]->id);
+		} else {
+			printf("\t%d -> %d\n", n->id, n->out.data[i]->id);
+		}
+	}
+	for (int i = 0; i < n->out.len; i++) {
+		node_print(n->out.data[i]);
+	}
+}
+
+void proc_print(Proc *p) {
+	if (p->start) {
+		printf("\t\"%.*s\" -> %d\n", (int)p->name.n, p->name.s, p->start->id);
+		node_print(p->start);
+		if (no_opt) {
+			for (NameBinding *b = p->scope.free_bind; b; b = b->prev) {
+				uint64_t id = (uintptr_t)b->node;
+				printf("\t\t%lu [label=\"%.*s\",shape=none,fontcolor=blue]\n", id, (int)b->name.n, b->name.s);
+				printf("\t\t%lu -> %d [arrowhead=none,style=dotted,color=blue]\n", id, b->node->id);
+			}
+		}
+	}
+}
+
+void unit_print(Unit *u) {
+	puts("digraph {");
+	for (int i = 0; i < u->procs.len; i++) {
+		proc_print(&u->procs.data[i]);
+	}
+	puts("}");
+}
+
+/* main */
+
 int main(int argc, const char **argv) {
 	if (argc != 2) {
 		fprintf(stderr, "Usage: %s FILE\n", argv[0]);