Specify lifetime parameter for serde deserialiser

1 
struct S1<T> 
{
    pub data: T
}
    
impl<'a, T> S1<T> where T: Deserialize<'a> {
    fn update() {
        let str_json = String::new(); // let's assume read from file
        self.data = serve_json::from_str(&str_json).unwrap();
    } 
}

this function will produce lifetime related issue due to incorrect specifier. What is the best way to overcome the problem?

2

You can't. If the deserialized value is borrowed (and that's what the lifetime specifier in Deserialize means), then the value it's borrowing from - the str_json, in this case - must be alive at least as long as the deserialized value itself. You want to either using DeserializeOwned instead of Deserialize<'a>, or pass the String to update function, with the second way being considerably harder.

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