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An implementation must document the character scripts it supports. For each character script supported, the documentation must describe at least the following:
Character labels, glyphs, and descriptions. Character labels must be uniquely named using only Latin capital letters A–Z, hyphen (-), and digits 0–9.
Reader canonicalization. Any mechanisms by which read treats different characters as equivalent must be documented.
The impact on char-upcase, char-downcase, and the case-sensitive format directives. In particular, for each character with case, whether it is uppercase or lowercase, and which character is its equivalent in the opposite case.
The behavior of the case-insensitive functions char-equal, char-not-equal, char-lessp, char-greaterp, char-not-greaterp, and char-not-lessp.
The behavior of any character predicates; in particular, the effects of alpha-char-p, lower-case-p, upper-case-p, both-case-p, graphic-char-p, and alphanumericp.
The interaction with file I/O, in particular, the supported coded character sets (for example, ISO8859/1-1987) and external encoding schemes supported are documented.