Struct FieldSpec 

pub struct FieldSpec {
    pub ty: Option<FieldType>,
    pub values: OpenClosed,
    pub vocabulary: Option<String>,
    pub reify: bool,
}

A field declaration — an entry in the fields block. It promotes a frontmatter field (tags, audience, created) that prov would otherwise merely carry (DESIGN §2, tier 3) into something prov and its frontends know the shape of. Two independent things can be declared, and a field needs at least one of them to be worth an entry:

• A type (ty) — what the value is. Pure data shape, decidable from the value alone, so it is spelled in fig-schema’s vocabulary rather than one prov invents.
• A vocabulary (vocabulary) — which values are legal, turning the field into a resolvable reference prov keeps consistent: every value is checked against the vocabulary document the pointer reaches.

They compose (a closed vocabulary of strings is both), but neither implies the other: created is a date with no vocabulary, and a vocabulary field needs no declared type.

Fields

ty: Option<FieldType>

The type the field’s values are expected to take, if declared. Drives type-directed parsing and widget choice in a frontend (a date field gets a date picker); prov itself carries it without interpreting it.

values: OpenClosed

Whether the value set is open (folksonomy) or closed (must be known). Meaningful only alongside a vocabulary.

vocabulary: Option<String>

The pointer (a link) to the vocabulary document listing this field’s legal terms — resolved like the registry/config pointers (DESIGN §6). None for a field that declares a type but no controlled vocabulary.

reify: bool

Whether each term is reified as its own node (rich: backlinks, a prose body, stable id) rather than a bare key in a flat registry. A hint to tooling; prov validates membership either way.

Trait Implementations

impl Clone for FieldSpec

fn clone(&self) -> FieldSpec

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FieldSpec

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for FieldSpec

impl PartialEq for FieldSpec

fn eq(&self, other: &FieldSpec) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for FieldSpec