Function from_env_seed 

pub fn from_env_seed<'de, D>(seed: D) -> Result<D::Value, Error>
where
    D: Copy + DeserializeSeed<'de>,

Deserialize from env::args() using a seed.

This function parses the command line arguments using the provided seed. On success a value of type D::Value is returned; on failure an Error is returned instead.

Note that the type D must also implement Copy. This is because the deserialization process requires visiting a type multiple times. If your seed type does not implement Copy, you will not be able to use this function.

Example

This example reads an integer from the command line and adding it to the seed value. The program returns early if an error is encountered.

use serde::de::{
    Deserialize,
    DeserializeSeed,
    Deserializer,
};

#[derive(Clone, Copy)]
struct Seed(u32);

impl<'de> DeserializeSeed<'de> for Seed {
    type Value = u32;

    fn deserialize<D>(self, deserializer: D) -> Result<Self::Value, D::Error>
    where
        D: Deserializer<'de>,
    {
        u32::deserialize(deserializer).map(|value| value + self.0)
    }
}

fn main() {
    let value = match serde_args::from_env_seed(Seed(42)) {
        Ok(value) => value,
        Err(error) => {
            println!("{error}");
            return;
        }
    };
    // Execute your program with `value`...
}