Crate borsh

Crate features

Ecosystem features

• std - When enabled, borsh uses the standard library. Disabling this feature will result in building the crate in no_std environment.

  To carter such builds, Borsh offers io module which includes a items which are used in BorshSerialize and BorshDeserialize traits. Most notably io::Read, io::Write and io::Result.

  When std feature is enabled, those items are re-exports of corresponding std::io items. Otherwise they are borsh-specific types which mimic behaviour of corresponding standard types.

Default features

• std - enabled by default.

Other features

• derive - Gates derive macros of BorshSerialize and BorshDeserialize traits.

• unstable__schema - Gates BorshSchema trait and its derive macro. Gates schema module. This feature requires derive to be enabled too.

• rc - Gates implementation of BorshSerialize and BorshDeserialize for Rc<T>/Arc<T> respectively. In no_std setting Rc/Arc are pulled from alloc crate. Serializing and deserializing these types does not preserve identity and may result in multiple copies of the same data. Be sure that this is what you want before enabling this feature.

• hashbrown - Pulls in HashMap/HashSet when no std is available. This feature is set to be mutually exclusive with std feature.

• bytes - Gates implementation of BorshSerialize and BorshDeserialize for Bytes and BytesMut.

• bson - Gates implementation of BorshSerialize and BorshDeserialize for ObjectId.

• indexmap - Gates implementation of BorshSerialize and BorshDeserialize for indexmap::IndexMap and IndexSet

• ascii - Gates implementation of BorshSerialize, BorshDeserialize, BorshSchema for types from ascii crate.

• de_strict_order - Enables check that keys, parsed during deserialization of HashMap/HashSet and BTreeSet/BTreeMap are encountered in ascending order with respect to PartialOrd for hash collections, and Ord for btree ones. Deserialization emits error otherwise.

  If this feature is not enabled, it is possible that two different byte slices could deserialize into the same HashMap/HashSet object.

Config aliases

• hash_collections - This is a feature alias, set up in build.rs to be equivalent to (std OR hashbrown). Gates implementation of BorshSerialize, BorshDeserialize and BorshSchema for HashMap/HashSet.

Shortcuts

Following pages are highlighted here just to give reader a chance at learning that they exist.

• Derive Macro BorshSerialize
• Derive Macro BorshDeserialize
• Derive Macro BorshSchema

Re-exports

pub use de::BorshDeserialize;

pub use de::from_reader;

pub use de::from_slice;

pub use schema::BorshSchema;

pub use ser::BorshSerialize;

Modules

de

error

io

Subset of std::io which is used as part of borsh public API.

schema

Module is available if borsh is built with features = ["unstable__schema"].

ser

Functions

max_serialized_size

Returns the largest possible size of a serialised object based solely on its type T.

object_length

Serializes an object without allocation to compute and return its length

schema_container_of

generate BorshSchemaContainer for type T

to_vec

Serialize an object into a vector of bytes.

to_writer

Serializes an object directly into a Writer.

try_from_slice_with_schema

Deserialize this instance from a slice of bytes, but assume that at the beginning we have bytes describing the schema of the type. We deserialize this schema and verify that it is correct.

try_to_vec_with_schema

Serialize object into a vector of bytes and prefix with the schema serialized as vector of bytes in Borsh format.

Derive Macros

BorshDeserialize

Derive macro available if borsh is built with features = ["derive"].

BorshSchema

Derive macro available if borsh is built with features = ["unstable__schema"].

BorshSerialize

Derive macro available if borsh is built with features = ["derive"].