Struct NoteAttachmentScheme 

pub struct NoteAttachmentScheme(/* private fields */);

The user-defined scheme of a NoteAttachment.

A note attachment scheme is an arbitrary 16-bit unsigned integer (max Self::MAX). It is intended to be used to distinguish one attachment from another, or find a specific attachment in a note’s attachments.

The scheme is purely a hint, and there is no validation with respect to the attachment content. In other words, any scheme can be associated with any attachment content. Hence, users should always validate the contents of an attachment, just like with NoteStorage.

Value 0 is reserved to signal that the entire attachment is absent and so it is not a valid scheme.

Value 1 is reserved to signal that the scheme is none. Whenever the kind of attachment is not standardized or interoperability is unimportant, this none value can be used.

Implementations

impl NoteAttachmentScheme

pub const MAX: NoteAttachmentScheme

The maximum value for a note attachment scheme.

Limited to 2^16 - 2 = 65534 to ensure the felt encoding remains valid when four schemes are packed into a single felt in the note metadata. Limiting schemes to this value means at least one bit is always unset which ensures felt validity.

pub fn new(attachment_scheme: u16) -> Result<Self, NoteError>

Creates a new NoteAttachmentScheme from a u16.

Errors

Returns an error if attachment_scheme is equal to 0 or exceeds Self::MAX.

pub const fn new_const(attachment_scheme: u16) -> Self

Creates a new NoteAttachmentScheme from a u16.

Panics

Panics if attachment_scheme is 0 or exceeds Self::MAX.

pub const fn none() -> Self

Returns the NoteAttachmentScheme that signals the absence of an attachment scheme.

pub const fn is_none(&self) -> bool

Returns true if the attachment scheme is the reserved value that signals an absent scheme, false otherwise.

pub const fn as_u16(&self) -> u16

Returns the note attachment scheme as a u16.

Trait Implementations

impl Clone for NoteAttachmentScheme

fn clone(&self) -> NoteAttachmentScheme

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NoteAttachmentScheme

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for NoteAttachmentScheme

fn default() -> Self

Returns NoteAttachmentScheme::none.

impl Deserializable for NoteAttachmentScheme

fn read_from<R: ByteReader>( source: &mut R, ) -> Result<Self, DeserializationError>

Reads a sequence of bytes from the provided source, attempts to deserialize these bytes into Self, and returns the result.

fn min_serialized_size() -> usize

Returns the minimum serialized size for one instance of this type.

fn read_from_bytes(bytes: &[u8]) -> Result<Self, DeserializationError>

Attempts to deserialize the provided bytes into Self and returns the result.

fn read_from_bytes_with_budget( bytes: &[u8], budget: usize, ) -> Result<Self, DeserializationError>

Deserializes Self from bytes with a byte budget limit.

impl Display for NoteAttachmentScheme

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<NoteAttachmentScheme> for NoteAttachmentHeader

fn from(scheme: NoteAttachmentScheme) -> Self

Converts to this type from the input type.

impl PartialEq for NoteAttachmentScheme

fn eq(&self, other: &NoteAttachmentScheme) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serializable for NoteAttachmentScheme

fn write_into<W: ByteWriter>(&self, target: &mut W)

Serializes self into bytes and writes these bytes into the target.

fn get_size_hint(&self) -> usize

Returns an estimate of how many bytes are needed to represent self.

fn to_bytes(&self) -> Vec<u8>

Serializes self into a vector of bytes.

impl TryFrom<u16> for NoteAttachmentScheme

type Error = NoteError

The type returned in the event of a conversion error.

fn try_from(value: u16) -> Result<Self, Self::Error>

Performs the conversion.

impl Copy for NoteAttachmentScheme

impl Eq for NoteAttachmentScheme

impl StructuralPartialEq for NoteAttachmentScheme