clippy::inspect_for_each: called `inspect(..).for_each(..)` on an `Iterator`

What you see

warning: called `inspect(..).for_each(..)` on an `Iterator`
 --> main.rs:4:2
  |
4 |   .inspect(|&x| println!("inspect the number: {}", x))
  |  __^
5 | | .for_each(|&x| {
6 | |     assert!(x >= 0);
7 | | });
  | |__^
  |
  = help: move the code from `inspect(..)` to `for_each(..)` and remove the `inspect(..)`
  = help: for further information visit https://rust-lang.github.io/rust-clippy/stable/index.html#inspect_for_each
  = note: `#[warn(clippy::inspect_for_each)]` on by default

Real output of Clippy 0.1.99 (Rust 1.99) on the example below. Names and line numbers in yours will differ.

Does it matter?

It is the same as performing the computation inside inspect at the beginning of the closure in for_each.

Code that does something simple in a complicated way. Warns by default.

How to fix it

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

Flagged

[1,2,3,4,5].iter()
.inspect(|&x| println!("inspect the number: {}", x))
.for_each(|&x| {
    assert!(x >= 0);
});

Write this instead

[1,2,3,4,5].iter()
.for_each(|&x| {
    println!("inspect the number: {}", x);
    assert!(x >= 0);
});

Turn it off, or on

Allow it where it does not fit your code, as narrowly as you can:

#[allow(clippy::inspect_for_each)]
fn my_function() { /* ... */ }

[lints.clippy]
inspect_for_each = "allow"

cargo clippy -- -A clippy::inspect-for-each

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.