llms.txt
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Address Type

Move uses a special type called address to represent addresses - the 32-byte values that identify accounts, packages, and objects on the blockchain. In an expression, an address literal starts with the @ symbol, followed either by a hexadecimal number or by an identifier:

// address literal
let value: address = @0x1;

// named address registered in Move.toml
let value = @std;
let other = @sui;

The hexadecimal number is interpreted as a 32-byte value, with the missing leading bytes filled with zeros - so @0x2 is a shorthand for the address ending in ...0002. The identifier is looked up in the Move.toml file and replaced with the corresponding address by the compiler; if it is not found there, compilation fails.

Some addresses are reserved by the system: for example, the Standard Library lives at 0x1 and the Sui Framework at 0x2. The full list is in Appendix B: Reserved Addresses.

Conversion​

Sui Framework offers a set of helper functions to work with addresses. Given that the address type is a 32-byte value, it can be converted to a u256 type and vice versa. It can also be converted to and from a vector<u8> type.

The examples below use the vector and String types, which are covered later in this chapter - for now, it is enough to know that a conversion to and from bytes and text exists.

Example: Convert an address to a u256 type and back.

use sui::address;

let addr_as_u256: u256 = @0x1.to_u256();
let addr = address::from_u256(addr_as_u256);

Example: Convert an address to a vector<u8> type and back.

use sui::address;

let addr_as_u8: vector<u8> = @0x1.to_bytes();
let addr = address::from_bytes(addr_as_u8);

Example: Convert an address into a string.

use sui::address;
use std::string::String;

let addr_as_string: String = @0x1.to_string();

Further Reading​

llms.txt