Expand description
Reference conversions (borrowed views into R vectors).
Provides zero-copy access to R vector data through references. Callers must keep the source SEXP rooted for the entire reference lifetime.
Covers: &T, &mut T, Option<&T>, Vec<&T>, Vec<&[T]>, and
mutable variants for all RNativeType types.
§Tradeoff
Prefer borrowed &[T] over owned Vec<T> when you only need read access —
this is the fast path (no allocation, no copy). Reach for &mut [T] only
when you genuinely need to mutate R-owned data in place; the R caller will
observe those writes (ALTREP MAYBE_REFERENCED rules still apply). Failure
mode: taking &mut [T] from a shared SEXP that R has handed to multiple
callers writes through that aliased buffer.
For NA-aware reads use crate::from_r::na_vectors (Vec<Option<T>>) —
borrowed slices cannot express NA without losing the sentinel encoding.
Outbound borrowed slices copy into R-owned storage through crate::IntoR.
Mutable list inputs preflight all raw ranges before creating any references;
this does not establish the root lifetime or exclude borrows held elsewhere
by a direct caller (the remaining lifetime-boundary work is #1427).
Macros§
Structs§
- Mutable
Range 🔒 - An unborrowed native buffer. No Rust reference exists during list preflight.
Functions§
- map_
mutable_ 🔒list - Validate every element and every raw buffer before creating any references. Different ALTREP objects can expose identical or partially overlapping storage, so comparing SEXP identities (or just starting pointers) is not enough here. NULL is a missing element only for the optional forms.