Function kanji::is_kanji

pub fn is_kanji(c: &char) -> bool

Kanji appear in the Unicode range 4e00 to 9ffc. The final Japanese Kanji is 9fef (鿯).

For a chart of the full official range, see this pdf from the Unicode organization.

A number of Level Pre-One Kanji appear in the CJK Compatibility Ideographs list, so there is an extra check here for those.

assert!(kanji::is_kanji(&'澄'));  // Obviously a legal Kanji.
assert!(!kanji::is_kanji(&'a'));  // Obviously not.