Module struct_enum_dispatch 

Dispatch #[miniextendr] on structs and enums to the appropriate derive helpers.

This module handles #[miniextendr] when applied to structs or enums (not functions, impl blocks, or traits). It dispatches to the correct derive helper based on:

• Item shape (structs → ExternalPtr, fieldless enums → RFactor by default)
• Explicit mode attributes (list, dataframe, externalptr, match_arg, factor)
• Preference markers (prefer = "...")

Disambiguation table

Syntax	Result
#[miniextendr] / #[miniextendr(externalptr)] on struct	ExternalPtr
#[miniextendr(list)] on struct	IntoList + TryFromList + PreferList
#[miniextendr(dataframe)] on struct	DataFrameRow (companion has IntoR)
#[miniextendr(prefer = "list" / "dataframe" / "externalptr")] on struct	Same as the explicit mode
#[miniextendr(prefer = "native")] on struct	ExternalPtr without its IntoR + PreferRNativeType
#[miniextendr(class = "...", base = "...")] on struct	Error: use an ALTREP derive
#[miniextendr] on fieldless enum	RFactor
#[miniextendr(match_arg)] on fieldless enum	MatchArg

Structs

StructEnumAttrs 🔒

Parsed attributes for #[miniextendr] on structs/enums.

Functions

expand_enum 🔒

Dispatches #[miniextendr] on a fieldless enum to the correct derive path.

expand_struct 🔒

Dispatches #[miniextendr] on a struct to the correct derive path.

expand_struct_or_enum

Main dispatch entry point for #[miniextendr] on a struct or enum.

is_fieldless_enum 🔒

Returns true if every variant of the enum is a unit variant (no fields).

parse_attrs 🔒

Parses the attribute arguments of #[miniextendr(...)] when applied to a struct or enum.

strip_miniextendr_attrs 🔒

Strip #[miniextendr(...)] attributes from a DeriveInput.