>  So SRFI 152’s procedure is both stricter and laxer than the R7RS
version.  I find this rather confusing.  It certainly presents a
headache for the plan to base R7RS-large’s string library on SRFI 152.

It might be too big for a PFN. However, having a SRFI-152bis
(SRFI-13bis²) that aligns the specification with common practice and
R7RS is a good idea. Then the modifications can be voted in to replace
SRFI 152 as the R7RS string library.

-- Peter McGoron