Standard Library

The Move Standard Library provides functionality for native types and operations. It is a standard collection of modules which do not interact with the storage, but provide basic tools for working and manipulating the data. It is the only dependency of the Sui Framework, and is imported together with it.

Most Common Modules

In this book we go into detail about most of the modules in the Standard Library, however, it is also helpful to give an overview of the features, so that you can get a sense of what is available and which module implements it.

Module	Description	Chapter
std::string	Provides basic string operations	String
std::ascii	Provides basic ASCII operations	String
std::option	Implements an `Option<T>`	Option
std::vector	Native operations on the vector type	Vector
std::bcs	Contains the `bcs::to_bytes()` function	BCS
std::address	Contains a single `address::length` function	Address
std::type_name	Allows runtime type reflection	Type Reflection
std::hash	Hashing functions: `sha2_256` and `sha3_256`	Cryptography and Hashing
std::debug	Contains debugging functions, which are available in only in test mode	Debugging
std::bit_vector	Provides operations on bit vectors	-
std::fixed_point32	Provides the `FixedPoint32` type	-

Integer Modules

The Move Standard Library provides a set of functions associated with integer types. These functions are split into multiple modules, each associated with a specific integer type. The modules should not be imported directly, but their functions are available on every integer value.

All of the modules provide the same set of functions. Namely, max, diff, divide_and_round_up, sqrt and pow.

Module	Description
std::u8	Functions for the `u8` type
std::16	Functions for the `u16` type
std::u32	Functions for the `u32` type
std::u64	Functions for the `u64` type
std::u128	Functions for the `u128` type
std::u256	Functions for the `u256` type

Exported Addresses

Standard Library exports one named address - std = 0x1.

[addresses]
std = "0x1"

Implicit Imports

Some of the modules are imported implicitly, and are available in the module without explicit use import. For Standard Library, these modules and types are:

std::vector
std::option
std::option::Option

Importing std without Sui Framework

The Move Standard Library can be imported to the package directly. However, std alone is not enough to build a meaningful application, as it does not provide any storage capabilities, and can't interact with the on-chain state.

MoveStdlib = { git = "https://github.com/MystenLabs/sui.git", subdir = "crates/sui-framework/packages/move-stdlib", rev = "framework/mainnet" }

Source Code

The source code of the Move Standard Library is available in the Sui repository.

The Move Book