This page is part of the web mail archives of SRFI 14 from before July 7th, 2015. The new archives for SRFI 14 contain all messages, not just those from before July 7th, 2015.
R5RS and all other procedures except ascii-range->char-set proposed in srfi-14 are defined so that they don't assume any specific character encoding. For example, char->integer may return different integer value from the same character on different implementations. So it is a bit weird for me that the spec explicitly refer to the ascii encoding in ascii-range->char-set. How about (integer-range->char-set LOWER UPPER), which contains every character on which the result of applying char->integer falls in the range of [LOWER, UPPER). The result is dependent on the internal character representation the implementation is using (but likely to be the same if you limit LOWER and UPPER in the range of the ascii code). I think char-set:ascii is fine, because it refers only to the ascii character set, not the ascii encoding. BTW, I prefer LIST->CHAR-SET to CHARS->CHAR-SET, for the former is consistent with its argument. -- Shiro KAWAI Square USA Inc. Honolulu Studio R&D division #"The most important things are the hardest things to say" --- Stephen King