Thanks to Justin Ethier, I've just published fixes for errata in the implementation of SRFI 113. They have been approved by John Cowan, the author of SRFI 113. There were no changes to the SRFI document.

Here are the comments from Justin's pull request:

Both calls incorrectly passed comparator as the second argument rather than the first arg.

For reference:

http://srfi.schemers.org/srfi-113/srfi-113.html#Mappingandfolding

https://github.com/scheme-requests-for-implementation/srfi-113/blob/master/sets/sets-impl.scm#L611

Commit Summary

Fix calls to `set-map` and `bag-map`.

File Changes

M sets/sets-test.scm (4)

Thank you, Justin.

— SRFI Editor