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MIT/GNU Scheme’s character-set abstraction is used to represent groups of characters, such as the letters or digits. A character set may contain any Unicode character.
Returns #t
if object is a character set; otherwise returns
#f
.
These variables contain predefined character sets. At present, these
character sets contain only ISO-8859-1 characters; in the
future they will contain all the relevant Unicode characters. To see
the contents of one of these sets, use char-set->scalar-values
.
Alphabetic characters are the 52 upper and lower case letters.
Numeric characters are the 10 decimal digits. Alphanumeric
characters are those in the union of these two sets. Whitespace
characters are #\space
, #\tab
, #\page
,
#\linefeed
, and #\return
. Graphic characters are
the printing characters and #\space
. Standard characters
are the printing characters, #\space
, and #\newline
.
These are the printing characters:
! " # $ % & ' ( ) * + , - . / 0 1 2 3 4 5 6 7 8 9 : ; < = > ? @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z [ \ ] ^ _ ` a b c d e f g h i j k l m n o p q r s t u v w x y z { | } ~
These predicates are defined in terms of the respective character sets defined above.
Returns #t
if char is in char-set; otherwise returns
#f
.
Returns #t
if char-set-1 and char-set-2 contain
exactly the same characters; otherwise returns #f
.
Returns a character set consisting of the specified characters. With no
arguments, char-set
returns an empty character set.
Returns a character set consisting of chars, which must be a list
of characters. This is equivalent to (apply char-set
chars)
.
Returns a character set consisting of all the characters that occur in string.
Returns a character set containing the Unicode scalar values described
by items. Items must satisfy
well-formed-scalar-values-list?
.
Returns a well-formed scalar-values list that describes the Unicode scalar values represented by char-set.
Returns #t
if object is a well-formed scalar-values list,
otherwise returns #f
. A well-formed scalar-values list is a
proper list, each element of which is either a Unicode scalar value or
a pair of Unicode scalar values. A pair of Unicode scalar values
represents a contiguous range of Unicode scalar values. The CAR
of the pair is the inclusive lower limit, and the CDR is the
exclusive upper limit. The lower limit must be less than or equal to
the upper limit.
Returns a character set consisting of the characters that are not in char-set.
Returns a character set consisting of the characters that are in char-set1 but aren’t in any of the char-sets.
Returns a character set consisting of the characters that are in all of the char-sets.
Returns a character set consisting of the characters that are in at least one o the char-sets.
Returns #t
if char-set contains only 8-bit scalar values
(i.e.. ISO-8859-1 characters), otherwise returns #f
.
This procedure is obsolete. Instead use
(scalar-values->char-set (list (cons lower upper)))
This procedure is obsolete; instead use char-set->scalar-values
.
Returns a newly allocated list of the ISO-8859-1 characters in char-set. If char-set contains any characters outside of the ISO-8859-1 range, they will not be in the returned list.
Next: Unicode, Previous: ISO-8859-1 Characters, Up: Characters [Contents][Index]