# Char Library The `(scheme char)` library provides the procedures for dealing with characters. For more information see the [R7RS Scheme Specification](../../r7rs.pdf). - [`char-alphabetic?`](#char-alphabetic?) - [`char-ci<=?`](#char-ci<=?) - [`char-ci=?`](#char-ci>=? ) - [`char-ci>?`](#char-ci>?) - [`char-downcase`](#char-downcase) - [`char-foldcase`](#char-foldcase) - [`char-lower-case?`](#char-lower-case?) - [`char-numeric?`](#char-numeric?) - [`char-upcase`](#char-upcase) - [`char-upper-case?`](#char-upper-case?) - [`char-whitespace?`](#char-whitespace?) - [`digit-value`](#digit-value) - [`string-ci<=?`](#string-ci<=? ) - [`string-ci=?`](#string-ci>=?) - [`string-ci>?`](#string-ci>? ) - [`string-downcase`](#string-downcase) - [`string-foldcase`](#string-foldcase) - [`string-upcase`](#string-upcase) #char-alphabetic? (char-alphabetic? c) #char-ci<=? (char-ci<=? c1 c2 . cs) #char-ci=? (char-ci>=? c1 c2 . cs) #char-ci>? (char-ci>? c1 c2 . cs) #char-downcase (char-downcase c) #char-foldcase (char-foldcase c) #char-lower-case? (char-lower-case? c) #char-numeric? (char-numeric? c) #char-upcase (char-upcase c) #char-upper-case? (char-upper-case? c) #char-whitespace? (char-whitespace? c) #digit-value (digit-value c) #string-ci<=? (string-ci<=? s1 s2) #string-ci=? (string-ci>=? s1 s2) #string-ci>? (string-ci>? s1 s2) #string-downcase (string-downcase str) #string-foldcase (string-foldcase str) #string-upcase (string-upcase str)