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1 min read Rust

TIL: Rust - Some(T) or T

Today i was asking myself a question with Optional in Rust, about the necessity to write some boilerplate code like this:

pub fn my_function(optional_input: Option<MyStruct>) {
    ...
}
...

let input = MyStruct::new();
my_function(input); // Doesn't compile
my_function(Some(input)); // Compile
my_function(None); // Compile

Okay even if it's little, that seems like unnecessary boilerplate to write the Some(x) part ?, like i know that there is "some" value here, so i started wondering:
Is there any way to write a function that take Option<T> or T and convert the T to Some(T) ?

Well, surprisingly enough i didn't find much about this on the internet, until i came across an old post on Reddit this article (the website wasn't even working, i had to go into the WebArchive to find more about)

And that's where i found the solution, something very simple.
A default implementation of Rust for From<T> for Option<T>

impl<T> From<T> for Option<T> {
    fn from(val: T) -> Option<T> {
        Some(val)
    }
}

The solution was indeed very simple:

pub fn my_function(optional_input: impl Into<Option<MyStruct>>) {
    let optional_input = optional_input.into();
    ...
}

let input = MyStruct::new();
my_function(input); // Compile
my_function(Some(input)); // Compile
my_function(None); // Compile

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