Trait RHash 

pub trait RHash {
    // Required method
    fn r_hash(&self) -> String;

    // Provided method
    #[doc(hidden)]
    unsafe extern "C" fn __RHash_r_hash_shim(
        data: *mut c_void,
        argc: i32,
        argv: *const SEXP,
    ) -> SEXP
       where Self: Sized + RHash { ... }
}

Adapter trait for std::hash::Hash.

Provides hashing for deduplication and environment keys in R. Automatically implemented for any type that implements Hash.

Methods

• r_hash() (hash() in R) - Returns the 64-bit hash as a 16-character hex string

Note

Hash values are deterministic within a single R session but may vary between sessions due to Rust’s hasher implementation.

The hash is returned as a hex String (e.g. "a1b2c3d4e5f60718"), not a number. R has no faithful 64-bit integer type, so returning the u64 as a numeric would round away its low bits above 2^53 — distinct Rust values would collide in R — and surface half the range as negative. A hex string preserves all 64 bits, is directly usable as an R environment key, and works with duplicated() / match() for deduplication.

Example

#[derive(Hash, ExternalPtr)]
struct Record { id: String, value: i64 }

#[miniextendr]
impl miniextendr_api::adapter_traits::RHash for Record {}

Required Methods

fn r_hash(&self) -> String

Compute a hash of this value.

Returns the DefaultHasher u64 output as a 16-character lowercase hex string. See the trait-level docs for why a string rather than a number.

Provided Methods

#[doc(hidden)]

unsafe extern "C" fn __RHash_r_hash_shim( data: *mut c_void, argc: i32, argv: *const SEXP, ) -> SEXP

where Self: Sized + RHash,

Method shim for RHash::r_hash.

Converts SEXP arguments, calls the method, and returns SEXP result. Both Rust panics and R longjmps are caught via with_r_unwind_protect.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<T: Hash> RHash for T