other
(in-package "STR")
other
(include-book "std/strings/charset" :dir :system)
other
(include-book "xdoc/constructors" :dir :system)
other
(local (include-book "std/basic/code-char-char-code-with-force" :dir :system))
other
(defcharset letter
(b* ((code (char-code x)))
(or (and (<= (char-code #\A) code)
(<= code (char-code #\Z)))
(and (<= (char-code #\a) code)
(<= code (char-code #\z)))))
:parents (character-kinds)
:short "Recognize ASCII letters."
:long (topstring (p "The built-in @(tsee alpha-char-p)
has a guard requiring characters.
In contrast, this recognizer has guard @('t').")))