Struct MapRef 

pub struct MapRef<'a> { /* private fields */ }

A borrowed view into a canonical CBOR map.

Map keys are text strings and appear in canonical order (encoded length then lexicographic byte order).

Implementations

impl<'a> MapRef<'a>

pub const fn len(self) -> usize

Returns the number of entries in the map.

pub const fn is_empty(self) -> bool

Returns whether the map is empty.

pub fn get(self, key: &str) -> Result<Option<CborValueRef<'a>>, CborError>

Looks up a single key in the map.

This is efficient for canonical maps: it scans entries once and can stop early.

Errors

Returns CborError if the map is malformed.

pub fn require(self, key: &str) -> Result<CborValueRef<'a>, CborError>

Looks up a required key in the map.

Errors

Returns CborError::MissingKey if the key is not present.

pub fn require_many_sorted<const N: usize>( self, keys: [&str; N], ) -> Result<[CborValueRef<'a>; N], CborError>

Looks up multiple required keys in a single pass.

Errors

Returns CborError::MissingKey if any key is not present.

pub fn get_many_sorted<const N: usize>( self, keys: [&str; N], ) -> Result<[Option<CborValueRef<'a>>; N], CborError>

Looks up multiple keys in a single pass.

Keys may be in any order; results preserve the input key order. Missing keys yield None.

Errors

Returns CborError for invalid query inputs or malformed canonical data.

pub fn get_many_sorted_into( self, keys: &[&str], out: &mut [Option<CborValueRef<'a>>], ) -> Result<(), CborError>

Available on crate feature alloc only.

The slice-based form of MapRef::get_many_sorted.

out is cleared to None for all entries before results are written.

Errors

Returns CborError for invalid query inputs or malformed canonical data.

pub fn iter( self, ) -> impl Iterator<Item = Result<(&'a str, CborValueRef<'a>), CborError>> + 'a

Iterates over (key, value) pairs in canonical order.

The iterator yields Result to remain robust if canonical invariants are violated.

pub fn extras_sorted<'k>( self, used_keys: &'k [&'k str], ) -> Result<impl Iterator<Item = Result<(&'a str, CborValueRef<'a>), CborError>> + 'k, CborError>

where 'a: 'k,

Iterates over map entries excluding used_keys (keys must be sorted canonically).

Errors

Returns CborError if used_keys are not strictly increasing or if the map is malformed.

pub fn extras_sorted_vec<'k>( self, used_keys: &'k [&'k str], ) -> Result<Vec<(&'a str, CborValueRef<'a>)>, CborError>

where 'a: 'k,

Available on crate feature alloc only.

Collects extras for sorted used_keys into a Vec.

Errors

Returns CborError if used_keys are not strictly increasing or if the map is malformed.

pub fn extras_vec<'k>( self, used_keys: &'k [&'k str], ) -> Result<Vec<(&'a str, CborValueRef<'a>)>, CborError>

where 'a: 'k,

Available on crate feature alloc only.

Accepts used_keys in any order (allocates to sort them), then returns extras.

Errors

Returns CborError if used_keys contain duplicates or if the map is malformed.

pub fn get_many( self, keys: &[&str], ) -> Result<Vec<Option<CborValueRef<'a>>>, CborError>

Available on crate feature alloc only.

Looks up multiple keys in one pass (keys may be in any order).

This API is available with the alloc feature. Results preserve the input key order.

Errors

Returns CborError for invalid query inputs or malformed canonical data.

pub fn require_many( self, keys: &[&str], ) -> Result<Vec<CborValueRef<'a>>, CborError>

Available on crate feature alloc only.

Looks up multiple required keys in one pass (keys may be in any order).

This API is available with the alloc feature. Results preserve the input key order.

Errors

Returns CborError::MissingKey if any key is not present.

pub fn get_many_into( self, keys: &[&str], out: &mut [Option<CborValueRef<'a>>], ) -> Result<(), CborError>

Available on crate feature alloc only.

The slice-based form of MapRef::get_many.

out is cleared to None for all entries before results are written.

Errors

Returns CborError for invalid query inputs or malformed canonical data.

Trait Implementations

impl<'a> Clone for MapRef<'a>

fn clone(&self) -> MapRef<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for MapRef<'a>

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

Formats the value using the given formatter.

impl<'a> Copy for MapRef<'a>