Clippy lints / Complexity
Clippy lint · Complexity · checked with Clippy 0.1.99
clippy::or_then_unwrap: Checks for .or(…).unwrap() calls to Options and Results
What it meansChecks for .or(…).unwrap() calls to Options and Results. It is in the complexity group and warns by default.
Does it matter?
You should use .unwrap_or(…) instead for clarity.
Code that does something simple in a complicated way. Warns by default.
How to fix it
Clippy can fix this one for you: run cargo clippy --fix (add --allow-dirty if you have uncommitted changes). Review the diff before you commit.
Flagged
// Result
let value = result.or::<Error>(Ok(fallback)).unwrap();
// Option
let value = option.or(Some(fallback)).unwrap();
Write this instead
// Result
let value = result.unwrap_or(fallback);
// Option
let value = option.unwrap_or(fallback);
Turn it off, or on
Allow it where it does not fit your code, as narrowly as you can:
On one item
#[allow(clippy::or_then_unwrap)]
fn my_function() { /* ... */ }Whole crate (Cargo.toml)
[lints.clippy]
or_then_unwrap = "allow"One run
cargo clippy -- -A clippy::or-then-unwrapThe [lints] table needs Rust 1.74 or newer. In a workspace, put it under [workspace.lints.clippy] and add [lints] workspace = true to each member.
Clippy's own documentation
What it does
Checks for .or(…).unwrap() calls to Options and Results.
Why is this bad?
You should use .unwrap_or(…) instead for clarity.
Example
// Result
let value = result.or::<Error>(Ok(fallback)).unwrap();
// Option
let value = option.or(Some(fallback)).unwrap();
Use instead:
// Result
let value = result.unwrap_or(fallback);
// Option
let value = option.unwrap_or(fallback);
From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.
Related lints
- too_many_argumentsChecks for functions with too many parameters
- clone_on_copyusing `clone` on type `u64` which implements the `Copy` trait
- type_complexityChecks for types used in structs, parameters and let declarations above a certain complexity threshold
- option_as_ref_derefChecks for usage of _.as_ref().map(Deref::deref) or its aliases (such as String::as_str)
- option_filter_map`filter` for `Some` followed by `unwrap`
- option_map_unit_fnChecks for usage of option.map(f) where f is a function or closure that returns the unit type ()
- partialeq_ne_implre-implementing `PartialEq::ne` is unnecessary
- precedenceChecks for operations where precedence may be unclear and suggests to add parentheses. It catches a mixed usage of arithmetic and bit shifting/combining operators, as well as method calls applied to closures
- ptr_offset_with_castuse of `offset` with a `usize` cast to an `isize`
All 847 Clippy lints · Rust compiler errors · Cargo.toml checker
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Related lintclippy::too_many_argumentsChecks for functions with too many parametersRead it next →Did this answer your question?