Enum Case 

#[non_exhaustive]
pub enum Case {
    Upper,
    Preserve,
}

How the case of names maps onto keys.

use std::collections::BTreeMap;
use deser_env::{Case, DeserializerConfig, SerializerConfig};

let vars = [("APP_Server__Port", "80")];
let value: BTreeMap<String, BTreeMap<String, u16>> =
    deser_env::from_vars("APP_", vars).unwrap();
assert_eq!(value["server"]["port"], 80);

let preserve = DeserializerConfig::builder().case(Case::Preserve).build();
let value: BTreeMap<String, BTreeMap<String, u16>> =
    preserve.from_vars("APP_", vars).unwrap();
assert_eq!(value["Server"]["Port"], 80);

let vars = deser_env::to_vars("APP_", &value).unwrap();
assert_eq!(vars, [("APP_SERVER__PORT".to_string(), "80".to_string())]);

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.

Upper

Names are upper case and keys lower case.

When deserializing names are lowercased (ASCII only), so APP_SERVER__PORT (and APP_server__port) is server.port. When serializing keys are uppercased. Keys of maps that are not lower case do not read back the same.

Preserve

Names and keys are the same.

This is useful if the types have names in upper case, for instance with #[deser(alias_all = "SCREAMING_SNAKE_CASE")].

Trait Implementations

impl Clone for Case

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Case

impl Debug for Case

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

Formats the value using the given formatter.

impl Default for Case

fn default() -> Self

Returns the “default value” for a type.

impl Eq for Case

impl PartialEq for Case

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for Case