fold should (optionally) warn on sequential processing

Question

It would be great to have a flag similar to warn-on-reflection but for fold to warn when it reduces sequentially (not parallel).

Answer 1

Comment made by: jare

Not sure what are requirements for fold to be parallelized but if it's associativity of the collection then the issue can be resolved by mentioning "associative?" predicate in the fold's doc-string.

Answer 2

Reference: https://clojure.atlassian.net/browse/CLJ-2370 (reported by alex+import)