Node:Characters,
Next:Strings,
Previous:Numbers,
Up:Simple Data Types
21.3 Characters
Most of the characters in the ASCII character set may be referred to by
name: for example, #\tab, #\esc, #\stx, and so on.
The following table describes the ASCII names for each character.
0 = #\nul
| 1 = #\soh
| 2 = #\stx
| 3 = #\etx
|
4 = #\eot
| 5 = #\enq
| 6 = #\ack
| 7 = #\bel
|
8 = #\bs
| 9 = #\ht
| 10 = #\nl
| 11 = #\vt
|
12 = #\np
| 13 = #\cr
| 14 = #\so
| 15 = #\si
|
16 = #\dle
| 17 = #\dc1
| 18 = #\dc2
| 19 = #\dc3
|
20 = #\dc4
| 21 = #\nak
| 22 = #\syn
| 23 = #\etb
|
24 = #\can
| 25 = #\em
| 26 = #\sub
| 27 = #\esc
|
28 = #\fs
| 29 = #\gs
| 30 = #\rs
| 31 = #\us
|
32 = #\sp
|
The delete character (octal 177) may be referred to with the name
#\del.
Several characters have more than one name:
#\space, #\sp
#\newline, #\nl
#\tab, #\ht
#\backspace, #\bs
#\return, #\cr
#\page, #\np
#\null, #\nul
| char? x
|
Scheme Procedure |
| scm_char_p (x)
|
C Function |
Return #t iff x is a character, else #f.
|
| char=? x y
|
Scheme Procedure |
Return #t iff x is the same character as y, else #f.
|
| char<? x y
|
Scheme Procedure |
Return #t iff x is less than y in the ASCII sequence,
else #f.
|
| char<=? x y
|
Scheme Procedure |
Return #t iff x is less than or equal to y in the
ASCII sequence, else #f.
|
| char>? x y
|
Scheme Procedure |
Return #t iff x is greater than y in the ASCII
sequence, else #f.
|
| char>=? x y
|
Scheme Procedure |
Return #t iff x is greater than or equal to y in the
ASCII sequence, else #f.
|
| char-ci=? x y
|
Scheme Procedure |
Return #t iff x is the same character as y ignoring
case, else #f.
|
| char-ci<? x y
|
Scheme Procedure |
Return #t iff x is less than y in the ASCII sequence
ignoring case, else #f.
|
| char-ci<=? x y
|
Scheme Procedure |
Return #t iff x is less than or equal to y in the
ASCII sequence ignoring case, else #f.
|
| char-ci>? x y
|
Scheme Procedure |
Return #t iff x is greater than y in the ASCII
sequence ignoring case, else #f.
|
| char-ci>=? x y
|
Scheme Procedure |
Return #t iff x is greater than or equal to y in the
ASCII sequence ignoring case, else #f.
|
| char-alphabetic? chr
|
Scheme Procedure |
| scm_char_alphabetic_p (chr)
|
C Function |
Return #t iff chr is alphabetic, else #f.
Alphabetic means the same thing as the isalpha C library function.
|
| char-numeric? chr
|
Scheme Procedure |
| scm_char_numeric_p (chr)
|
C Function |
Return #t iff chr is numeric, else #f.
Numeric means the same thing as the isdigit C library function.
|
| char-whitespace? chr
|
Scheme Procedure |
| scm_char_whitespace_p (chr)
|
C Function |
Return #t iff chr is whitespace, else #f.
Whitespace means the same thing as the isspace C library function.
|
| char-upper-case? chr
|
Scheme Procedure |
| scm_char_upper_case_p (chr)
|
C Function |
Return #t iff chr is uppercase, else #f.
Uppercase means the same thing as the isupper C library function.
|
| char-lower-case? chr
|
Scheme Procedure |
| scm_char_lower_case_p (chr)
|
C Function |
Return #t iff chr is lowercase, else #f.
Lowercase means the same thing as the islower C library function.
|
| char-is-both? chr
|
Scheme Procedure |
| scm_char_is_both_p (chr)
|
C Function |
Return #t iff chr is either uppercase or lowercase, else #f.
Uppercase and lowercase are as defined by the isupper and islower
C library functions.
|
| char->integer chr
|
Scheme Procedure |
| scm_char_to_integer (chr)
|
C Function |
|
Return the number corresponding to ordinal position of chr in the
ASCII sequence.
|
| integer->char n
|
Scheme Procedure |
| scm_integer_to_char (n)
|
C Function |
|
Return the character at position n in the ASCII sequence.
|
| char-upcase chr
|
Scheme Procedure |
| scm_char_upcase (chr)
|
C Function |
|
Return the uppercase character version of chr.
|
| char-downcase chr
|
Scheme Procedure |
| scm_char_downcase (chr)
|
C Function |
|
Return the lowercase character version of chr.
|