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Comment by bobbylarrybobby | Hacker News Reader

You can also de-mut-ify a variable by simply shadowing it with an immutable version of itself:

let mut data = foo(); data.mutate(); let data = data;

May be preferable for short snippets where adding braces, the yielded expression, and indentation is more noise than it's worth.

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Variable shadowing felt wrong for a while because it's considered verboten in so many other environments. I use it fairly liberally in rust now.

It helps that the specific pattern of redeclaring a variable just to change its mutability for the remainder of its scope is about the least objectionable use of shadowing possible.

That's not the only place I use shadowing though. I use it much more liberally.

For example I feel this is right:

    let x = x.parse()?;

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