Struct QuotedTriplesSignal 

pub struct QuotedTriplesSignal {
    pub present: bool,
    pub export_surfaces: Vec<String>,
    pub export_default: Option<String>,
}

Whether the file contains quoted triples — statements standing inside other statements — and, if it does, what a consumer gets when they export it.

This is the question “will I meet triple terms in this dataset, and in which spelling?”, which a consumer needs answered before they download a 50 GB file and run rete export on it. The two surfaces are not interchangeable downstream: an RDF 1.2 parser rejects <<s p o>> in N-Quads and silently reads it as a reifier in Turtle/TriG, and an RDF-star parser rejects <<( s p o )>> everywhere. Which one a dump carries decides whether it loads at all, so it belongs in the card rather than in the reader’s memory of a CLI flag.

Measured at read time from the header, never stored, exactly like TextIndexSignal and PermutationsSignal, and for the sharpest version of the same reason: header flag bit 2 (FLAG_HAS_QUOTED_TRIPLES) has been written by every build since quoted triples were supported, so this is an honest answer for every file that already exists — the 44 published datasets included — with no re-card and no rebuild. A stored copy would be null on all of them, which is worse than nothing: it would assert “unknown” about files whose own header knows.

None therefore means unknown — a card read out of a saved JSON document, with no file to measure — and never “no quoted triples”.

There is deliberately no count. The header carries presence, not cardinality, and counting would mean decoding the dictionary — outside the CARD tier’s budget (header + metadata, never the dictionary), and available only to files built after this existed, which is the failure mode above.

Fields

present: bool

Does the file hold at least one quoted triple as a dictionary term?

export_surfaces: Vec<String>

The surfaces rete export can write them in, most interoperable first. Empty when present is false: the question does not arise.

export_default: Option<String>

Which of export_surfaces rete export writes with no flag. None when present is false.

Implementations

impl QuotedTriplesSignal

pub fn probe(header: &Header) -> Self

Read it straight off the parsed header — flag bit 2, in the 1 KiB every card read has already fetched. No range read of any kind.

pub fn describe(&self) -> Option<String>

One line for the human catalog view, or None when there is nothing to say — most datasets have no quoted triples, and a card should not grow a line per affordance they do not use.

Trait Implementations

impl Clone for QuotedTriplesSignal

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for QuotedTriplesSignal

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for QuotedTriplesSignal

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for QuotedTriplesSignal

impl PartialEq for QuotedTriplesSignal

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for QuotedTriplesSignal

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for QuotedTriplesSignal