Struct StableTypeId 

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

An opaque holder for a stable, deterministic identifier for a Rust type.

Implementations

impl StableTypeId

pub fn for_type<T>() -> StableTypeId

Returns the stable string key associated with type T.

Overview

This function produces a deterministic, globally stable identifier for a Rust type by returning the fully-qualified name produced by core::any::type_name.

The resulting key is:

• Bijective – each distinct type maps to a distinct string key.
• Deterministic – the same type always produces the same key within a given version of this crate.
• Pure – no side effects; does not depend on runtime state.
• Compilation-unit stable – the returned value does not depend on memory layout, type IDs, or other non-portable properties.

This key is used internally by the serializable anymap to index entries by their type. Because TypeId is not stable across compilation units or compiler versions, string keys offer a portable alternative suitable for serialization.

Stability Guarantees

Changing the implementation of this function is to be considered a breaking change

Consumers relying on serialized output can therefore depend on this value as a long-term stable identifier for the type.

Caveats

The current implementatino relies on std::any::type_name, which is NOT guaranteed to be stable across rustc versions, although change is unlikely.

Examples

use anymap_serde::StableTypeId;

let k1 = StableTypeId::for_type::<i32>();
let k2 = StableTypeId::for_type::<Option<String>>();

assert_eq!(format!("{}", k1), "i32");
assert_eq!(format!("{}", k2), "core::option::Option<alloc::string::String>");

Notes

• The function returns an owned String rather than a &'static str, because the underlying representation from type_name is returned as a borrowed string and needs to be materialized for storage.
• For generic types, the key includes full type parameters in a canonical format.

See Also

• core::any::type_name – the underlying mechanism used to generate the key.

Returns

A stable, deterministic string key uniquely identifying the type T.

Trait Implementations

impl Clone for StableTypeId

fn clone(&self) -> StableTypeId

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StableTypeId

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for StableTypeId

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for StableTypeId

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

Formats the value using the given formatter.

impl Hash for StableTypeId

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for StableTypeId

fn cmp(&self, other: &StableTypeId) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for StableTypeId

fn eq(&self, other: &StableTypeId) -> 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 PartialOrd for StableTypeId

fn partial_cmp(&self, other: &StableTypeId) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for StableTypeId

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for StableTypeId

impl StructuralPartialEq for StableTypeId