Node:SRFI-14 Standard Character Sets, Previous:SRFI-14 Character-Set Algebra, Up:SRFI-14

39.12.8 Standard Character Sets

In order to make the use of the character set data type and procedures useful, several predefined character set variables exist.

char-set:lower-case Variable
All lower-case characters.

char-set:upper-case Variable
All upper-case characters.

char-set:title-case Variable
This is empty, because ASCII has no titlecase characters.

char-set:letter Variable
All letters, e.g. the union of char-set:lower-case and char-set:upper-case.

char-set:digit Variable
All digits.

char-set:letter+digit Variable
The union of char-set:letter and char-set:digit.

char-set:graphic Variable
All characters which would put ink on the paper.

char-set:printing Variable
The union of char-set:graphic and char-set:whitespace.

char-set:whitespace Variable
All whitespace characters.

char-set:blank Variable
All horizontal whitespace characters, that is #\space and #\tab.

char-set:iso-control Variable
The ISO control characters with the codes 0-31 and 127.

char-set:punctuation Variable
The characters !"#%&'()*,-./:;?@[\\]_{}

char-set:symbol Variable
The characters $+<=>^`|~.

char-set:hex-digit Variable
The hexadecimal digits 0123456789abcdefABCDEF.

char-set:ascii Variable
All ASCII characters.

char-set:empty Variable
The empty character set.

char-set:full Variable
This character set contains all possible characters.