RS.CLIPPY.FROM_OVER_INTO

Warns on implementations of `Into<..>` to use `From<..>`

This checker is a Clippy lint created by The Rust Project Contributors. The documentation shown here is a copy of the original documentation for: from_over_into. Copyright ©2025 The Rust Team. All rights reserved.

What it does

Searches for implementations of the Into<..> trait and suggests to implement From<..> instead.

Why is this bad?

According the std docs implementing From<..> is preferred since it gives you Into<..> for free where the reverse isn't true.

Example

struct StringWrapper(String);

impl Into<StringWrapper> for String {
    fn into(self) -> StringWrapper {
        StringWrapper(self)
    }
}

Use instead:

struct StringWrapper(String);

impl From<String> for StringWrapper {
    fn from(s: String) -> StringWrapper {
        StringWrapper(s)
    }
}

Configuration

msrv: The minimum rust version that the project supports. Defaults to the rust-version field in Cargo.toml

(default: current version)