Module codec 

Compact binary encoding for UBT nodes.

All node types use a 1-byte type tag prefix:

Tag	Type	Size
0x00	Empty	1 byte
0x01	Internal	65 bytes (tag + two 32B hashes)
0x02	Stem	64 + N×32 bytes (tag + stem + bitmap + values)
0x03	Leaf	33 bytes (tag + 32B value)

StemNode layout

[1B type=0x02] [31B stem] [32B bitmap] [N×32B values]

Bitmap: 256 bits, bit i set = subindex i present. Bit ordering: byte[i/8] & (1 << (i%8)). Values in ascending subindex order, only for set bits.

Enums

DecodedNode

A decoded node from the wire format.

Constants

EMPTY_NODE_TAG

Type tag for empty nodes.

INTERNAL_NODE_TAG

Type tag for internal nodes (two child hashes).

LEAF_NODE_TAG

Type tag for leaf nodes (single value).

STEM_NODE_TAG

Type tag for stem nodes (bitmap + values).

Functions

decode_internal_node

Decode an internal node from [0x01] [32B left_hash] [32B right_hash].

decode_leaf_node

Decode a leaf node from [0x03] [32B value].

decode_node

Decode any node type by dispatching on the type tag.

decode_stem_node

Decode a StemNode from compact binary format.

encode_empty_node

Encode an empty node as [0x00].

encode_internal_node

Encode an internal node as [0x01] [32B left_hash] [32B right_hash].

encode_leaf_node

Encode a leaf node as [0x03] [32B value].

encode_stem_node

Encode a StemNode into compact binary format.

encoded_stem_size

Returns the encoded size of a stem node without allocating.