1 files changed, 46 insertions, 0 deletions
diff --git a/inc/tree.h b/inc/tree.h
new file mode 100644
index 0000000..8f11f1b
--- /dev/null
+++ b/inc/tree.h
@@ -0,0 +1,46 @@
+// Copyright (c) 2023, Marvin Borner <dev@marvinborner.de>
+// SPDX-License-Identifier: MIT
+
+#ifndef BLOC_TREE_H
+#define BLOC_TREE_H
+
+#include <stdint.h>
+
+#include <term.h>
+
+#define VALIDATED_TREE ((int)0x0)
+#define INVALIDATED_TREE ((int)0xffffffff)
+#define FREEABLE_TREE(t)                                                       \
+	((t)->state != VALIDATED_TREE && (t)->state != INVALIDATED_TREE)
+
+struct tree {
+	term_type type;
+	uint32_t hash;
+	int state; // zero or index to ref
+	int size; // blc length
+	union {
+		struct {
+			struct tree *term;
+		} abs;
+		struct {
+			struct tree *lhs;
+			struct tree *rhs;
+		} app;
+		struct {
+			int index;
+		} var;
+		struct {
+			size_t index;
+		} ref;
+	} u;
+};
+
+struct list {
+	int val; // length or priority
+	void *data;
+	struct list *next;
+};
+
+struct list *tree_merge_duplicates(struct term *term);
+
+#endif