U256 decimal string ser/de

u256_fromstr_radix_10.rs

pub mod u256_fromstr_radix_10 {
    use super::*;

    pub fn deserialize<'de, D>(deserializer: D) -> Result<U256, D::Error>
    where
        D: Deserializer<'de>,
    {
        struct Helper;

        impl<'de> Visitor<'de> for Helper {
            type Value = U256;

            fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
                formatter.write_str("a string")
            }

            fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
            where
                E: serde::de::Error,
            {
                U256::from_dec_str(value).map_err(serde::de::Error::custom)
            }
        }

        deserializer.deserialize_str(Helper)
    }

    pub fn serialize<S>(value: &U256, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        serializer.collect_str(&value)
    }
}