# Module BSV::Transaction::VarInt <a id="module-BSV-Transaction-VarInt"></a>

Bitcoin variable-length integer encoding/decoding.

VarInts encode unsigned integers compactly: values under 253 use a single
byte; larger values use a marker byte followed by 2, 4, or 8 bytes in
little-endian order.

## Constants
### `MAX_UINT64` <a id="constant-MAX_UINT64"></a> <a id="MAX_UINT64-constant"></a>
Maximum value representable by a Bitcoin VarInt (unsigned 64-bit).

## Public Class Methods
### `decode(data, offset = 0)` <a id="method-c-decode"></a> <a id="decode-class_method"></a>
Decode a Bitcoin VarInt from binary data at the given offset.
- **@param** `data` [String] binary data containing the VarInt
- **@param** `offset` [Integer] byte offset to start reading from
- **@raise** [ArgumentError]
- **@return** [Array(Integer, Integer)] the decoded value and number of bytes consumed

### `encode(value)` <a id="method-c-encode"></a> <a id="encode-class_method"></a>
Encode an integer as a Bitcoin VarInt.
- **@param** `value` [Integer] non-negative integer to encode (0..2^64-1)
- **@raise** [ArgumentError] if +value+ is negative or exceeds 2^64-1
- **@return** [String] encoded binary bytes