Clippy lint · Restriction · checked with Clippy 0.1.99

clippy::question_mark_used: Checks for expressions that use the ? operator and rejects them

What it meansChecks for expressions that use the ? operator and rejects them. It is in the restriction group and off by default.

Does it matter?

Sometimes code wants to avoid the ? operator because for instance a local block requires a macro to re-throw errors to attach additional information to the error.

Lints that forbid language features for specific codebases (no unwrap, no indexing...). Off by default; pick them one by one, never the whole group.

How to fix it

Clippy does not fix this one automatically. Change the code by hand:

Flagged

let result = expr?;

Write this instead

utility_macro!(expr);

Turn it off, or on

It is off by default. To use it, set it to warn or deny:

Whole crate (Cargo.toml)

[lints.clippy]
question_mark_used = "warn"

In code

#![warn(clippy::question_mark_used)]

One run

cargo clippy -- -W clippy::question-mark-used

The [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.

Restrictiongroup

allowdefault level

nofixed by cargo clippy --fix

1.69.0added in Rust

Clippy's own documentation

What it does

Checks for expressions that use the ? operator and rejects them.

Why restrict this?

Sometimes code wants to avoid the ? operator because for instance a local block requires a macro to re-throw errors to attach additional information to the error.

Example

let result = expr?;

Could be written:

utility_macro!(expr);

From the Clippy lint list (0.1.99), part of the Rust project, MIT or Apache-2.0. Official entry.

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