Struct OptionDeclMetadata 

pub struct OptionDeclMetadata {
    pub name: &'static str,
    pub doc: &'static str,
    pub customizable: bool,
    pub group_name: &'static str,
    pub type_label: fn() -> &'static str,
    pub default_formatted: fn() -> String,
    pub type_id: fn() -> TypeId,
    pub register_fn: fn(&ConfigRegistry),
}

Metadata captured at macro expansion for one option. The register function pointer is monomorphised at the call site so the registry boot path can register every option without pulling each <T> into a generic over the slice.

register_fn returns () and inserts the option into the crate::ConfigRegistry it is handed (via crate::ConfigRegistry::register_with_typeid); crate::ConfigRegistry::init_from_linkme calls it once per element of OPTION_DECLS.

Also the data the browse surfaces read without a registry: :customize groups by Self::group_name and hides entries whose Self::customizable is false.

Fields

name: &'static str

The option’s OptionDecl::NAME — its :set / TOML key.

doc: &'static str

The option’s OptionDecl::DOC.

customizable: bool

The option’s OptionDecl::CUSTOMIZABLE; false hides it from :customize.

group_name: &'static str

The owning group’s display name (HasGroup::GROUP_NAME), which :customize <group> matches against.

type_label: fn() -> &'static str

&'static str produced by the value type’s OptionType::type_label – captured as a function pointer so the slice element can be a static (the trait method isn’t const, so calling it directly in a static initializer fails). Resolved at the registry boot loop; cheap (one function call per option, once).

default_formatted: fn() -> String

Format the type’s default value for diagnostic surfaces (:describe-option “default: X”). Captured as a function pointer so the slice element stays object-safe-shaped.

type_id: fn() -> TypeId

TypeId::of::<Self>() for the declaration type. Same as <T as OptionDecl>::type_id() at the macro call site; pre-computed so the boot loop doesn’t pay the indirection.

register_fn: fn(&ConfigRegistry)

Self-registration thunk. Called by the registry’s init_from_linkme boot loop with the registry as argument; the thunk constructs the runtime crate::option::Option<T> spec via Self::build_spec() and calls registry.register_with_typeid. The register_fn is generated by the crate::options! macro and captures the option’s type identity at compile time. Boot panics (with the option’s name in the message) if any registration fails – duplicate names at startup are a build-config bug.

Implementations

impl OptionDeclMetadata

pub const fn for_decl<D: OptionDecl + HasGroup>( type_label: fn() -> &'static str, default_formatted: fn() -> String, register_fn: fn(&ConfigRegistry), ) -> Self

Construct a metadata record for the given declaration type. Helper used by the crate::options! macro’s generated code; not intended for hand-call.