Struct HeaderMap 

pub struct HeaderMap { /* private fields */ }

A list of (name, value) pairs in insertion order.

Implementations

impl HeaderMap

pub fn new() -> Self

Create an empty map.

pub fn with_capacity(n: usize) -> Self

Create a map with capacity for n entries (no allocations until exceeded).

pub fn append( &mut self, name: impl Into<HeaderName>, value: impl Into<HeaderValue>, )

Append (name, value) to the map. Allows duplicate names — use this only for headers that are semantically multi-valued (Set-Cookie, Via, etc.). For the common case of “set this header to this value”, use Self::insert.

pub fn insert( &mut self, name: impl Into<HeaderName>, value: impl Into<HeaderValue>, )

Set name to value, replacing any existing entries with the same name. Matches http::HeaderMap::insert / reqwest::HeaderMap::insert semantics: a single entry with this name will exist after the call.

The new entry is placed at the position of the first existing match (preserving header order when overwriting), otherwise appended.

pub fn remove<N: AsHeaderName>(&mut self, name: N) -> usize

Remove all entries matching name. Returns the count removed.

pub fn get<N: AsHeaderName>(&self, name: N) -> Option<&HeaderValue>

First value matching name, if any.

pub fn get_all<N: AsHeaderName>( &self, name: N, ) -> impl Iterator<Item = &HeaderValue>

All values matching name, in insertion order.

pub fn contains_key<N: AsHeaderName>(&self, name: N) -> bool

Whether at least one entry matches name.

pub fn iter(&self) -> impl Iterator<Item = (&HeaderName, &HeaderValue)>

Iterate entries in insertion order.

pub fn len(&self) -> usize

Number of entries (counts duplicates).

pub fn is_empty(&self) -> bool

Whether the map is empty.

pub fn extend(&mut self, other: HeaderMap)

Append all entries from other in their original order. Duplicates are preserved (this does not deduplicate against self).

pub fn merge_replacing(&mut self, other: HeaderMap)

Append all entries from other, with later names winning over earlier ones in self. Within other, all entries are kept (even duplicate names).

Trait Implementations

impl Clone for HeaderMap

fn clone(&self) -> HeaderMap

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HeaderMap

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

Formats the value using the given formatter.

impl Default for HeaderMap

fn default() -> HeaderMap

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for HeaderMap

fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error>

Deserialize this value from the given Serde deserializer.

impl Eq for HeaderMap

impl From<&HeaderMap> for HeaderMap

fn from(value: &ReqMap) -> Self

Converts to this type from the input type.

impl From<HeaderMap> for HeaderMap

fn from(value: HeaderMap) -> Self

Converts to this type from the input type.

impl FromIterator<(HeaderName, HeaderValue)> for HeaderMap

fn from_iter<I: IntoIterator<Item = (HeaderName, HeaderValue)>>(iter: I) -> Self

Creates a value from an iterator.

impl IntoIterator for HeaderMap

type Item = (HeaderName, HeaderValue)

The type of the elements being iterated over.

type IntoIter = IntoIter<<HeaderMap as IntoIterator>::Item>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<'a> IntoIterator for &'a HeaderMap

type Item = (&'a HeaderName, &'a HeaderValue)

The type of the elements being iterated over.

type IntoIter = Map<Iter<'a, (HeaderName, HeaderValue)>, fn(&'a (HeaderName, HeaderValue)) -> (&'a HeaderName, &'a HeaderValue)>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl PartialEq for HeaderMap

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for HeaderMap

fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error>

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for HeaderMap