Struct BoundedString 

pub struct BoundedString<const N: usize> { /* private fields */ }

Bounded UTF-8 string for Hopper dynamic tails.

This is the common migration target for bounded string account metadata. It keeps a fixed [u8; N] backing buffer, carries a small length prefix on the tail wire, and validates UTF-8 when read as &str.

Implementations

impl<const N: usize> BoundedString<N>

pub const fn empty() -> BoundedString<N>

Construct an empty bounded string.

pub fn from_str(value: &str) -> Result<BoundedString<N>, ProgramError>

Construct from UTF-8 bytes, rejecting values longer than N.

pub fn from_bytes(value: &[u8]) -> Result<BoundedString<N>, ProgramError>

Construct from bytes, rejecting values longer than N.

pub fn set_str(&mut self, value: &str) -> Result<(), ProgramError>

Replace the contents in place.

pub fn set_bytes(&mut self, value: &[u8]) -> Result<(), ProgramError>

Replace the contents in place.

pub fn clear(&mut self)

Clear the string without changing its capacity.

pub fn as_bytes(&self) -> &[u8]

Return the initialized bytes.

pub fn as_str(&self) -> Result<&str, ProgramError>

Return the initialized bytes as UTF-8.

pub const fn len(&self) -> usize

Number of initialized bytes.

pub const fn capacity(&self) -> usize

Maximum byte capacity.

pub const fn remaining_capacity(&self) -> usize

Remaining byte capacity.

pub const fn is_full(&self) -> bool

Whether the string has reached its maximum byte capacity.

pub const fn is_empty(&self) -> bool

Whether the string is empty.

Trait Implementations

impl<const N: usize> Clone for BoundedString<N>

fn clone(&self) -> BoundedString<N>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<const N: usize> Default for BoundedString<N>

fn default() -> BoundedString<N>

Returns the “default value” for a type.

impl<const N: usize> PartialEq for BoundedString<N>

fn eq(&self, other: &BoundedString<N>) -> 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<const N: usize> TailCodec for BoundedString<N>

const MAX_ENCODED_LEN: usize

Upper bound on the encoded size. Used by generated helpers to verify the account has enough room before invoking encode. Implementors should pick the smallest valid bound. Hopper uses this to pre-size reallocs.

fn encode(&self, out: &mut [u8]) -> Result<usize, ProgramError>

Serialize self into out. Returns the number of bytes written (always <= MAX_ENCODED_LEN). Fails with AccountDataTooSmall when out.len() < encoded_len.

fn decode(input: &[u8]) -> Result<(BoundedString<N>, usize), ProgramError>

Deserialize from input. Returns (value, bytes_consumed). Fails with InvalidAccountData on malformed encoding.

impl<const N: usize> Copy for BoundedString<N>

impl<const N: usize> Eq for BoundedString<N>

impl<const N: usize> StructuralPartialEq for BoundedString<N>