Credence.Rule.NoListFold
(credence v0.3.1)
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Detects usage of List.foldl/3 and List.foldr/3 and suggests
Enum.reduce/3 instead.
Why this matters
Enum.reduce/3 is the idiomatic Elixir way to fold over a collection.
While List.foldl/3 and List.foldr/3 exist in Elixir's standard
library, they are rarely used in practice and signal code ported from
Erlang (:lists.foldl) or Haskell.
LLMs frequently generate List.foldl because their training data
includes heavy Erlang and Haskell influence. The resulting code is
functionally correct but non-idiomatic, which reduces readability for
Elixir developers.
Flagged patterns
| Pattern | Suggested replacement |
|---|---|
List.foldl/3 | Enum.reduce/3 |
List.foldr/3 | Enum.reduce/3 (with Enum.reverse/1) |