Module core 

Core ALTREP data traits and helpers.

Defines shared infrastructure used by all ALTREP families:

• AltrepLen — length query trait
• AltrepDataptr / AltrepSerialize / AltrepExtractSubset — optional capabilities
• InferBase — maps data types to their R base type + class registration
• Sortedness — sort-order metadata constants
• Logical — three-valued logical (TRUE/FALSE/NA)
• fill_region — helper for get_region implementations

Enums

Logical

Logical value: TRUE, FALSE, or NA.

Sortedness

Sortedness hint for ALTREP vectors.

Traits

AltrepDataptr

Trait for ALTREP types that can expose a data pointer.

AltrepExtract

How to extract a reference to Self from an ALTREP SEXP’s data1 slot.

AltrepExtractSubset

Trait for ALTREP types that can provide optimized subsetting.

AltrepLen

Base trait for ALTREP data types. All ALTREP types must provide length.

AltrepSerialize

Trait for ALTREP types that support serialization.

InferBase

Trait for inferring the R base type from a data type’s implemented traits.

Functions

fill_region 🔒

Helper for ALTREP get_region implementations.

materialize_altrep_data2^⚠

Materialize an ALTREP SEXP into a plain R vector in data2.