rust-lang / rust-lang/rust-clippy

Does not detect redundant use of collect + iter + map

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A-lint L-complexity
Dominant language
Rust
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Description

There might be reasons this is not always the case, however, it seems like a situation when I was being far too verbose and an opportunity for clippy to let me know. Here is the verbose version of the code:

   (1..=64)
        .collect::<Vec<_>>()
        .iter()
        .map(|&sq| square(sq))
        .sum()

Here is the pithy version of the code:

    (1..=64).map(square).sum()

- E

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Research direction

Start by searching rust-clippy for existing lints that inspect iterator chains involving collect, iter, and map, then compare their testing patterns with the two examples in this issue. Done means the redundant chain is detected and a suggestion for the direct map-and-sum form is covered by tests.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
tooling
Issue type
Feature
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
42/100

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