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(guile.info)Characters

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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

 - primitive: char? x
     Return `#t' iff X is a character, else `#f'.

 - primitive: char=? x y
     Return `#t' iff X is the same character as Y, else `#f'.

 - primitive: char<? x y
     Return `#t' iff X is less than Y in the ASCII sequence, else `#f'.

 - primitive: char<=? x y
     Return `#t' iff X is less than or equal to Y in the ASCII
     sequence, else `#f'.

 - primitive: char>? x y
     Return `#t' iff X is greater than Y in the ASCII sequence, else
     `#f'.

 - primitive: char>=? x y
     Return `#t' iff X is greater than or equal to Y in the ASCII
     sequence, else `#f'.

 - primitive: char-ci=? x y
     Return `#t' iff X is the same character as Y ignoring case, else
     `#f'.

 - primitive: char-ci<? x y
     Return `#t' iff X is less than Y in the ASCII sequence ignoring
     case, else `#f'.

 - primitive: char-ci<=? x y
     Return `#t' iff X is less than or equal to Y in the ASCII sequence
     ignoring case, else `#f'.

 - primitive: char-ci>? x y
     Return `#t' iff X is greater than Y in the ASCII sequence ignoring
     case, else `#f'.

 - primitive: char-ci>=? x y
     Return `#t' iff X is greater than or equal to Y in the ASCII
     sequence ignoring case, else `#f'.

 - primitive: char-alphabetic? chr
     Return `#t' iff CHR is alphabetic, else `#f'.  Alphabetic means
     the same thing as the isalpha C library function.

 - primitive: char-numeric? chr
     Return `#t' iff CHR is numeric, else `#f'.  Numeric means the same
     thing as the isdigit C library function.

 - primitive: char-whitespace? chr
     Return `#t' iff CHR is whitespace, else `#f'.  Whitespace means
     the same thing as the isspace C library function.

 - primitive: char-upper-case? chr
     Return `#t' iff CHR is uppercase, else `#f'.  Uppercase means the
     same thing as the isupper C library function.

 - primitive: char-lower-case? chr
     Return `#t' iff CHR is lowercase, else `#f'.  Lowercase means the
     same thing as the islower C library function.

 - primitive: char-is-both? chr
     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.

 - primitive: char->integer chr
     Return the number corresponding to ordinal position of CHR in the
     ASCII sequence.

 - primitive: integer->char n
     Return the character at position N in the ASCII sequence.

 - primitive: char-upcase chr
     Return the uppercase character version of CHR.

 - primitive: char-downcase chr
     Return the lowercase character version of CHR.