Struct serde_with::NoneAsEmptyString [−][src]
pub struct NoneAsEmptyString;
Expand description
De/Serialize a Option<String>
type while transforming the empty string to None
Convert an Option<T>
from/to string using FromStr
and AsRef<str>
implementations.
An empty string is deserialized as None
and a None
vice versa.
The same functionality is also available as serde_with::rust::string_empty_as_none
compatible with serde’s with-annotation.
Examples
#[serde_as]
#[derive(Deserialize, Serialize)]
struct A {
#[serde_as(as = "NoneAsEmptyString")]
tags: Option<String>,
}
let v: A = serde_json::from_value(json!({ "tags": "" })).unwrap();
assert_eq!(None, v.tags);
let v: A = serde_json::from_value(json!({ "tags": "Hi" })).unwrap();
assert_eq!(Some("Hi".to_string()), v.tags);
let x = A {
tags: Some("This is text".to_string()),
};
assert_eq!(json!({ "tags": "This is text" }), serde_json::to_value(&x).unwrap());
let x = A {
tags: None,
};
assert_eq!(json!({ "tags": "" }), serde_json::to_value(&x).unwrap());
Trait Implementations
Returns the “default value” for a type. Read more
impl<'de, Str> DeserializeAs<'de, Option<Str>> for NoneAsEmptyString where
Str: FromStr,
Str::Err: Display,
impl<'de, Str> DeserializeAs<'de, Option<Str>> for NoneAsEmptyString where
Str: FromStr,
Str::Err: Display,
fn deserialize_as<D>(deserializer: D) -> Result<Option<Str>, D::Error> where
D: Deserializer<'de>,
fn deserialize_as<D>(deserializer: D) -> Result<Option<Str>, D::Error> where
D: Deserializer<'de>,
Deserialize this value from the given Serde deserializer.
fn serialize_as<S>(
source: &Option<AsRefStr>,
serializer: S
) -> Result<S::Ok, S::Error> where
S: Serializer,
fn serialize_as<S>(
source: &Option<AsRefStr>,
serializer: S
) -> Result<S::Ok, S::Error> where
S: Serializer,
Serialize this value into the given Serde serializer.
Auto Trait Implementations
impl RefUnwindSafe for NoneAsEmptyString
impl Send for NoneAsEmptyString
impl Sync for NoneAsEmptyString
impl Unpin for NoneAsEmptyString
impl UnwindSafe for NoneAsEmptyString
Blanket Implementations
Mutably borrows from an owned value. Read more