Module char

Function cmp

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

Compare two chars

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:

• Tab, CR and LF are escaped as '\t', '\r' and '\n' respectively.
• Single-quote, double-quote and backslash chars are backslash-escaped.
• Any other chars in the range [0x20,0x7e] are not escaped.
• Any other chars are given hex unicode escapes; see escape_unicode.

Function escape_unicode

fn escape_unicode(c: char) -> str

Return the hexadecimal unicode escape of a char.

The rules are as follows:

• chars in [0,0xff] get 2-digit escapes: \\\\xNN
• chars in [0x100,0xffff] get 4-digit escapes: \\\\uNNNN
• chars above 0x10000 get 8-digit escapes: \\\\UNNNNNNNN

Function is_XID_continue

pure fn XID_Continue(c: char) -> bool

Function is_XID_start

pure fn XID_Start(c: char) -> bool

Function is_alphabetic

pure fn Alphabetic(c: char) -> bool

Check if a character has the alphabetic unicode property

Function is_alphanumeric

pure fn is_alphanumeric(c: char) -> bool

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

Function is_ascii

pure fn is_ascii(c: char) -> bool

Indicates whether the character is an ASCII character

Function is_digit

pure fn is_digit(c: char) -> bool

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

Function is_lowercase

pure 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

pure 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

pure fn is_whitespace(c: char) -> bool

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

Function to_digit

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

Convert a char to the corresponding digit.