Struct AltrepBuffer

Source

pub struct AltrepBuffer<T: RNativeType> {
    values: Vec<T>,
    exposed: bool,
    retired: Vec<Vec<T>>,
}

Expand description

A growable native buffer whose exposed allocations survive later edits.

Wrap in Altrep to return it to R. Built-in classes use value semantics: R duplication clones the current values, so a copy R makes keeps its own values. An edit through the owner of an R object changes that object in place, for every binding R has of it.

edit detaches first if R has requested a data pointer, and keeps the old allocation until this owner is dropped. Previously returned pointers then refer to the prior values; subsequent callbacks see the new values. R provides no pointer-release notification, so repeated exposure followed by editing retains one buffer per such edit. No buffer is copied when it has only been read through Elt or Get_region.

This type deliberately has no DerefMut or method returning &mut Vec<T>: growth must pass through the edit boundary.

Fields§

§values: Vec<T>§exposed: bool§retired: Vec<Vec<T>>

Struct AltrepBuffer Copy item path

Fields§

Implementations§

impl<T: RNativeType> AltrepBuffer<T>

pub fn new(values: Vec<T>) -> Self

pub fn as_slice(&self) -> &[T]

pub fn edit<R>(&mut self, edit: impl FnOnce(&mut Vec<T>) -> R) -> R

pub fn len(&self) -> usize

pub fn capacity(&self) -> usize

pub fn is_empty(&self) -> bool

Trait Implementations§

impl AltComplex for AltrepBuffer<Rcomplex>

const HAS_ELT: bool = true

const HAS_GET_REGION: bool = true

fn elt(x: SEXP, i: R_xlen_t) -> Rcomplex

fn get_region( x: SEXP, start: R_xlen_t, len: R_xlen_t, buf: &mut [Rcomplex], ) -> R_xlen_t

impl AltComplexData for AltrepBuffer<Rcomplex>

fn elt(&self, i: usize) -> Rcomplex

fn as_slice(&self) -> Option<&[Rcomplex]>

fn get_region(&self, start: usize, len: usize, buf: &mut [Rcomplex]) -> usize

impl AltInteger for AltrepBuffer<i32>

const HAS_ELT: bool = true

const HAS_GET_REGION: bool = true

const HAS_IS_SORTED: bool = true

const HAS_NO_NA: bool = true

const HAS_SUM: bool = true

const HAS_MIN: bool = true

const HAS_MAX: bool = true

fn elt(x: SEXP, i: R_xlen_t) -> i32

fn get_region( x: SEXP, start: R_xlen_t, len: R_xlen_t, buf: &mut [i32], ) -> R_xlen_t

fn is_sorted(x: SEXP) -> i32

fn no_na(x: SEXP) -> i32

fn sum(x: SEXP, narm: bool) -> SEXP

fn min(x: SEXP, narm: bool) -> SEXP

fn max(x: SEXP, narm: bool) -> SEXP

impl AltIntegerData for AltrepBuffer<i32>

fn elt(&self, i: usize) -> i32

fn as_slice(&self) -> Option<&[i32]>

fn get_region(&self, start: usize, len: usize, buf: &mut [i32]) -> usize

fn is_sorted(&self) -> Option<Sortedness>

fn no_na(&self) -> Option<bool>

fn sum(&self, _na_rm: bool) -> Option<i64>

fn min(&self, _na_rm: bool) -> Option<i32>

fn max(&self, _na_rm: bool) -> Option<i32>

impl AltLogical for AltrepBuffer<RLogical>

const HAS_ELT: bool = true

const HAS_GET_REGION: bool = true

const HAS_IS_SORTED: bool = true

const HAS_NO_NA: bool = true

const HAS_SUM: bool = true

fn elt(x: SEXP, i: R_xlen_t) -> i32

fn get_region( x: SEXP, start: R_xlen_t, len: R_xlen_t, buf: &mut [i32], ) -> R_xlen_t

fn is_sorted(x: SEXP) -> i32

fn no_na(x: SEXP) -> i32

fn sum(x: SEXP, narm: bool) -> SEXP

impl AltLogicalData for AltrepBuffer<RLogical>

fn elt(&self, i: usize) -> Logical

fn as_r_slice(&self) -> Option<&[i32]>

fn get_region(&self, start: usize, len: usize, buf: &mut [i32]) -> usize

fn is_sorted(&self) -> Option<Sortedness>

fn no_na(&self) -> Option<bool>

fn sum(&self, _na_rm: bool) -> Option<i64>

impl AltRaw for AltrepBuffer<u8>

const HAS_ELT: bool = true

const HAS_GET_REGION: bool = true

fn elt(x: SEXP, i: R_xlen_t) -> u8

fn get_region( x: SEXP, start: R_xlen_t, len: R_xlen_t, buf: &mut [u8], ) -> R_xlen_t

impl AltRawData for AltrepBuffer<u8>

fn elt(&self, i: usize) -> u8

fn as_slice(&self) -> Option<&[u8]>

fn get_region(&self, start: usize, len: usize, buf: &mut [u8]) -> usize

impl AltReal for AltrepBuffer<f64>

const HAS_ELT: bool = true

const HAS_GET_REGION: bool = true

const HAS_IS_SORTED: bool = true

const HAS_NO_NA: bool = true

const HAS_SUM: bool = true

const HAS_MIN: bool = true

const HAS_MAX: bool = true

fn elt(x: SEXP, i: R_xlen_t) -> f64

Struct AltrepBuffer