Struct OcrBackendCapabilities 

pub struct OcrBackendCapabilities {
    pub name: String,
    pub supported_languages: Vec<String>,
}

A registered OCR backend’s declared name and language capabilities.

Returned by list_ocr_backend_capabilities. See that function’s documentation for the determinism guarantees and the important caveat about what an empty supported_languages means.

Fields

name: String

The backend’s registered name, as returned by list_ocr_backends.

supported_languages: Vec<String>

The languages this backend declares support for, via OcrBackend::supported_languages.

An empty list means the backend does not enumerate its languages — it is not a statement that the backend supports no languages. OcrBackend::supported_languages is a defaulted trait method that returns vec![], and not every backend overrides it: the VLM backend (llm::vlm_ocr::VlmOcrBackend) accepts every language via supports_language while inheriting the empty default here. Use ocr_backend_supports_language to decide whether one specific language is usable — never infer “unsupported” from an empty list.

The order of this list is preserved exactly as the backend reported it and is not re-sorted. Tesseract’s order comes from enumerating installed tessdata files; PaddleOCR’s comes from its own SUPPORTED_LANGUAGES constant. Re-sorting would disagree with the precedence each backend’s own supports_language implementation uses internally.

This is the no-override answer (list_ocr_backend_capabilities). Use list_ocr_backend_capabilities_for when the caller sets OcrConfig.tessdata_path: for Tesseract the language list is a property of the resolved tessdata directory, and the no-override chain can name a different directory than the one a job using that config will load from. See GH#1857.

Trait Implementations

impl Clone for OcrBackendCapabilities

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 OcrBackendCapabilities

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for OcrBackendCapabilities

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for OcrBackendCapabilities

impl PartialEq for OcrBackendCapabilities

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for OcrBackendCapabilities

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 OcrBackendCapabilities