mirror of https://github.com/rust-lang/book
28 lines
1.3 KiB
Plaintext
28 lines
1.3 KiB
Plaintext
$ cargo run
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Compiling patterns v0.1.0 (file:///projects/patterns)
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error[E0005]: refutable pattern in local binding: `None` not covered
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--> src/main.rs:3:9
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3 | let Some(x) = some_option_value;
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| ^^^^^^^ pattern `None` not covered
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= note: `let` bindings require an "irrefutable pattern", like a `struct` or an `enum` with only one variant
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= note: for more information, visit https://doc.rust-lang.org/book/ch18-02-refutability.html
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note: `Option<i32>` defined here
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--> /rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/option.rs:518:1
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= note:
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/rustc/d5a82bbd26e1ad8b7401f6a718a9c57c96905483/library/core/src/option.rs:522:5: not covered
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= note: the matched value is of type `Option<i32>`
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help: you might want to use `if let` to ignore the variant that isn't matched
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3 | let x = if let Some(x) = some_option_value { x } else { todo!() };
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| ++++++++++ ++++++++++++++++++++++
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help: alternatively, you might want to use let else to handle the variant that isn't matched
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3 | let Some(x) = some_option_value else { todo!() };
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| ++++++++++++++++
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For more information about this error, try `rustc --explain E0005`.
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error: could not compile `patterns` due to previous error
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