Enum Crs 

#[non_exhaustive]
pub enum Crs {
    Unknown,
    Epsg(u32),
    Wkt(String),
    Projjson(String),
}

Coordinate reference system. Marked #[non_exhaustive] because future versions may add Wkt2(String), a structured Authority { name, code }, or pre-parsed PROJJSON without that counting as a SemVer-breaking change.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Unknown

CRS unknown or unspecified.

Epsg(u32)

An EPSG authority code (e.g. 4326, 7844).

Wkt(String)

Well-Known Text (ESRI-WKT or OGC-WKT). Stored verbatim.

Projjson(String)

PROJJSON. Stored verbatim (GeoParquet’s preferred form).

Implementations

impl Crs

pub fn is_unknown(&self) -> bool

pub fn epsg_code(&self) -> Option<u32>

Return the CRS as an EPSG authority code, if it can be cheaply determined. Resolution order:

1. Crs::Epsg returns directly.
2. Crs::Wkt looks for AUTHORITY["EPSG","NNNN"] (WKT1) or ID["EPSG",NNNN] (WKT2) on the outermost CRS node.
3. If no authority is present, fall back to a small inline lookup of common datum/CRS names (“GDA2020”, “WGS 84”, “NAD83”, “Web Mercator”, etc.) — handles the ESRI File-Geodatabase case where the WKT has just a name and a datum, no AUTHORITY.

Returns None for Crs::Unknown, Crs::Projjson, or WKT we can’t resolve. Full WKT → EPSG resolution (every CRS) requires PROJ and is the job of the future geonative-proj crate.

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

Render the CRS as PROJJSON — the form GeoParquet stores in its geo metadata. v0.1 produces a minimal PROJJSON that just references an EPSG code when one is detectable:

{ "$schema": "...", "type": "GeographicCRS", "id": { "authority": "EPSG", "code": 4326 } }

Returns None if no EPSG code is detectable. Full WKT → PROJJSON conversion (preserving every parameter) requires PROJ and is deferred to the optional geonative-proj crate; until then, the GeoParquet spec also accepts WKT in the crs field as a string fallback.

Trait Implementations

impl Clone for Crs

fn clone(&self) -> Crs

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Crs

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

Formats the value using the given formatter.

impl Default for Crs

fn default() -> Crs

Returns the “default value” for a type.

impl Eq for Crs

impl PartialEq for Crs

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Crs