Char Library

The (scheme char) library provides the procedures for dealing with characters.

For more information see the R7RS Scheme Specification.

char-alphabetic?

(char-alphabetic? c)

Return #t if c is alphabetic and #f otherwise.

char-ci<=?

(char-ci<=? c1 c2 . cs)

Return #t if the results of converting all characters to the same case and passing the arguments to char->integer are monotonically increasing or equal.

char-ci<?

(char-ci<? c1 c2 . cs)

Return #t if the results of converting all characters to the same case and passing the arguments to char->integer are respectively equal, monotonically increasing.

char-ci=?

(char-ci=? c1 c2 . cs)

Return #t if the results of converting all characters to the same case and passing the arguments to char->integer are equal.

char-ci>=?

(char-ci>=? c1 c2 . cs)

Return #t if the results of converting all characters to the same case and passing the arguments to char->integer are monotonically decreasing or equal.

char-ci>?

(char-ci>? c1 c2 . cs)

Return #t if the results of converting all characters to the same case and passing the arguments to char->integer are monotonically decreasing.

char-downcase

(char-downcase c)

Returns the lowercase equivalent of c if one exists, otherwise c is returned.

char-foldcase

(char-foldcase c)

char-lower-case?

(char-lower-case? c)

Return #t if c is lower case and #f otherwise.

char-numeric?

(char-numeric? c)

Return #t if c is numeric and #f otherwise.

char-upcase

(char-upcase c)

Returns the uppercase equivalent of c if one exists, otherwise c is returned.

char-upper-case?

(char-upper-case? c)

Return #t if c is alphabetic and #f otherwise.

char-whitespace?

(char-whitespace? c)

Return #t if c is whitespace and #f otherwise.

digit-value

(digit-value c)

This procedure returns the numeric value (0 to 9) of its argument if it is a numeric digit (that is, if char-numeric? returns #t), or #f on any other character.

string-ci<=?

(string-ci<=? s1 s2)

string-ci<?

(string-ci<? s1 s2)

string-ci=?

(string-ci=? s1 s2)

Returns #t if all of the given strings are equal using a case-insensitive comparison, and false otherwise.

string-ci>=?

(string-ci>=? s1 s2)

string-ci>?

(string-ci>? s1 s2)

string-downcase

(string-downcase str)

Return a newly-allocated string with any uppercase characters converted to lowercase.

string-foldcase

(string-foldcase str)

string-upcase

(string-upcase str)

Return a newly-allocated string with any lowercase characters converted to uppercase.