Utilities for manipulating the char type

Implementation of Eq for char

Method eq

fn eq(&self, other: &char) -> bool

Method ne

fn ne(&self, other: &char) -> bool

Function cmp

fn cmp(a: char, b: char) -> int

Compare two chars

Return value

-1 if a < b, 0 if a == b, +1 if a > b

Function escape_default

fn escape_default(c: char) -> ~str

Return a 'default' ASCII and C++11-like char-literal escape of a char.

The default is chosen with a bias toward producing literals that are legal in a variety of languages, including C++11 and similar C-family languages. The exact rules are:

Function escape_unicode

fn escape_unicode(c: char) -> ~str

Return the hexadecimal unicode escape of a char.

The rules are as follows:

Function from_digit

fn from_digit(num: uint, radix: uint) -> Option<char>

Converts a number to the ascii character representing it.

Returns Some(char) if num represents one digit under radix, using one character of 0-9 or a-z, or None if it doesn't.

Fails if given an radix > 36.

Function is_alphanumeric

fn is_alphanumeric(c: char) -> bool

Indicates whether a character is alphanumeric. Alphanumericness is defined in terms of the Unicode General Categories 'Nd', 'Nl', 'No' and the Derived Core Property 'Alphabetic'.

Function is_ascii

fn is_ascii(c: char) -> bool

Indicates whether the character is an ASCII character

Function is_digit

fn is_digit(c: char) -> bool

Indicates whether the character is numeric (Nd, Nl, or No)

Function is_digit_radix

fn is_digit_radix(c: char, radix: uint) -> bool

Checks if a character parses as a numeric digit in the given radix. Compared to is_digit(), this function only recognizes the ascii characters 0-9, a-z and A-Z.

Returns true if c is a valid digit under radix, and false otherwise.

Fails if given a radix > 36.

Note: This just wraps to_digit().

Function is_lowercase

fn is_lowercase(c: char) -> bool

Indicates whether a character is in lower case, defined in terms of the Unicode General Category 'Ll'

Function is_uppercase

fn is_uppercase(c: char) -> bool

Indicates whether a character is in upper case, defined in terms of the Unicode General Category 'Lu'.

Function is_whitespace

fn is_whitespace(c: char) -> bool

Indicates whether a character is whitespace. Whitespace is defined in terms of the Unicode General Categories 'Zs', 'Zl', 'Zp' additional 'Cc'-category control codes in the range [0x09, 0x0d]

Function to_digit

fn to_digit(c: char, radix: uint) -> Option<uint>

Convert a char to the corresponding digit.

Return value

If c is between '0' and '9', the corresponding value between 0 and 9. If c is 'a' or 'A', 10. If c is 'b' or 'B', 11, etc. Returns none if the char does not refer to a digit in the given radix.

Failure

Fails if given a radix outside the range [0..36].