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// Please also update README.md when making changes to this code.
use erased_serde::{Deserializer, Serialize, Serializer};
use std::collections::BTreeMap as Map;
use std::io;
#[test]
fn serialization() {
// Construct some serializers.
let json = &mut serde_json::Serializer::new(io::stdout());
let cbor = &mut serde_cbor::Serializer::new(serde_cbor::ser::IoWrite::new(io::stdout()));
// The values in this map are boxed trait objects. Ordinarily this would not
// be possible with serde::Serializer because of object safety, but type
// erasure makes it possible with erased_serde::Serializer.
let mut formats: Map<&str, Box<dyn Serializer>> = Map::new();
formats.insert("json", Box::new(<dyn Serializer>::erase(json)));
formats.insert("cbor", Box::new(<dyn Serializer>::erase(cbor)));
// These are boxed trait objects as well. Same thing here - type erasure
// makes this possible.
let mut values: Map<&str, Box<dyn Serialize>> = Map::new();
values.insert("vec", Box::new(vec!["a", "b"]));
values.insert("int", Box::new(65536));
// Pick a Serializer out of the formats map.
let format = formats.get_mut("json").unwrap();
// Pick a Serialize out of the values map.
let value = values.get("vec").unwrap();
// This line prints `["a","b"]` to stdout.
value.erased_serialize(format).unwrap();
}
#[test]
fn deserialization() {
static JSON: &[u8] = br#"{"A": 65, "B": 66}"#;
static CBOR: &[u8] = &[162, 97, 65, 24, 65, 97, 66, 24, 66];
// Construct some deserializers.
let json = &mut serde_json::Deserializer::from_slice(JSON);
let cbor = &mut serde_cbor::Deserializer::from_slice(CBOR);
// The values in this map are boxed trait objects, which is not possible
// with the normal serde::Deserializer because of object safety.
let mut formats: Map<&str, Box<dyn Deserializer>> = Map::new();
formats.insert("json", Box::new(<dyn Deserializer>::erase(json)));
formats.insert("cbor", Box::new(<dyn Deserializer>::erase(cbor)));
// Pick a Deserializer out of the formats map.
let format = formats.get_mut("json").unwrap();
let data: Map<String, usize> = erased_serde::deserialize(format).unwrap();
println!("{}", data["A"] + data["B"]);
}
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