Struct PerParamMiniextendrAttr 

pub(crate) struct PerParamMiniextendrAttr {
    pub has_coerce: bool,
    pub has_match_arg: bool,
    pub default_value: Option<(String, Span)>,
    pub choices: Option<Vec<String>>,
    pub has_several_ok: bool,
    pub has_no_default: bool,
    pub checks: ExplicitChecks,
    pub preconditions: Option<bool>,
    pub formal: Option<LitStr>,
}

Parsed per-parameter #[miniextendr(...)] attribute content.

A single attribute can contain multiple items, e.g. #[miniextendr(match_arg, default = "Safe")]; a parameter carrying several attributes gets them merged (PerParamMiniextendrAttr::merge).

Fields

has_coerce: bool

Whether coerce was present, enabling automatic type coercion for this parameter (e.g., i32 to u16, f64 to f32).

has_match_arg: bool

Whether match_arg was present, generating R match.arg() validation for string parameters against a set of allowed values.

default_value: Option<(String, Span)>

Default value from default = "...", if present. The tuple contains the default value string and the attribute span (for error reporting).

choices: Option<Vec<String>>

Choices for string parameters: #[miniextendr(choices("a", "b", "c"))].

has_several_ok: bool

Whether several_ok was present, enabling multi-value match.arg(several.ok = TRUE). Only valid with choices(...) or match_arg.

has_no_default: bool

Whether no_default was present: the choice parameter’s R formal has no default (#1828). Only valid with choices(...) or match_arg, and not together with default.

checks: ExplicitChecks

inherits = "cls" / inherits("a", "b"), not_inherits (the same spellings) and no_na, each with an optional message = "...": R-side checks named by the author (see crate::r_preconditions::ExplicitChecks).

preconditions: Option<bool>

preconditions / no_preconditions on the parameter (#1566): Some(true) keeps its type-derived R-side checks, Some(false) drops them. The last one written wins.

formal: Option<LitStr>

formal = "conf.int": the parameter’s R formal (#1842), checked by crate::r_wrapper_builder::check_r_formals.

Implementations

impl PerParamMiniextendrAttr

pub(crate) fn merge( &mut self, other: PerParamMiniextendrAttr, ) -> Result<(), String>

Merge the options of another attribute on the same parameter: flags add up, the first default / choices(...) wins, the last preconditions / no_preconditions wins, and the checks merge (one message per check; the error says which). A second formal is an error.

Trait Implementations

impl Default for PerParamMiniextendrAttr

fn default() -> Self

Returns the “default value” for a type.

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 232 bytes