rust/src/libcore/char.rs
2012-02-11 16:50:03 -08:00

253 lines
7.2 KiB
Rust

#[doc = "Utilities for manipulating the char type"];
/*
Lu Uppercase_Letter an uppercase letter
Ll Lowercase_Letter a lowercase letter
Lt Titlecase_Letter a digraphic character, with first part uppercase
Lm Modifier_Letter a modifier letter
Lo Other_Letter other letters, including syllables and ideographs
Mn Nonspacing_Mark a nonspacing combining mark (zero advance width)
Mc Spacing_Mark a spacing combining mark (positive advance width)
Me Enclosing_Mark an enclosing combining mark
Nd Decimal_Number a decimal digit
Nl Letter_Number a letterlike numeric character
No Other_Number a numeric character of other type
Pc Connector_Punctuation a connecting punctuation mark, like a tie
Pd Dash_Punctuation a dash or hyphen punctuation mark
Ps Open_Punctuation an opening punctuation mark (of a pair)
Pe Close_Punctuation a closing punctuation mark (of a pair)
Pi Initial_Punctuation an initial quotation mark
Pf Final_Punctuation a final quotation mark
Po Other_Punctuation a punctuation mark of other type
Sm Math_Symbol a symbol of primarily mathematical use
Sc Currency_Symbol a currency sign
Sk Modifier_Symbol a non-letterlike modifier symbol
So Other_Symbol a symbol of other type
Zs Space_Separator a space character (of various non-zero widths)
Zl Line_Separator U+2028 LINE SEPARATOR only
Zp Paragraph_Separator U+2029 PARAGRAPH SEPARATOR only
Cc Control a C0 or C1 control code
Cf Format a format control character
Cs Surrogate a surrogate code point
Co Private_Use a private-use character
Cn Unassigned a reserved unassigned code point or a noncharacter
*/
export is_alphabetic,
is_XID_start, is_XID_continue,
is_lowercase, is_uppercase,
is_whitespace, is_alphanumeric,
is_ascii, is_digit,
to_digit, to_lower, to_upper, maybe_digit, cmp;
import is_alphabetic = unicode::derived_property::Alphabetic;
import is_XID_start = unicode::derived_property::XID_Start;
import is_XID_continue = unicode::derived_property::XID_Continue;
#[doc(
brief = "Indicates whether a character is in lower case, defined \
in terms of the Unicode General Category 'Ll'."
)]
pure fn is_lowercase(c: char) -> bool {
ret unicode::general_category::Ll(c);
}
#[doc(
brief = "Indicates whether a character is in upper case, defined \
in terms of the Unicode General Category 'Lu'."
)]
pure fn is_uppercase(c: char) -> bool {
ret unicode::general_category::Lu(c);
}
#[doc(
brief = "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]"
)]
pure fn is_whitespace(c: char) -> bool {
ret ('\x09' <= c && c <= '\x0d')
|| unicode::general_category::Zs(c)
|| unicode::general_category::Zl(c)
|| unicode::general_category::Zp(c);
}
#[doc(
brief = "Indicates whether a character is alphanumeric, defined \
in terms of the Unicode General Categories 'Nd', \
'Nl', 'No' and the Derived Core Property 'Alphabetic'."
)]
pure fn is_alphanumeric(c: char) -> bool {
ret unicode::derived_property::Alphabetic(c) ||
unicode::general_category::Nd(c) ||
unicode::general_category::Nl(c) ||
unicode::general_category::No(c);
}
#[doc( brief = "Indicates whether the character is an ASCII character" )]
pure fn is_ascii(c: char) -> bool {
c - ('\x7F' & c) == '\x00'
}
#[doc( brief = "Indicates whether the character is numeric (Nd, Nl, or No)" )]
pure fn is_digit(c: char) -> bool {
ret unicode::general_category::Nd(c) ||
unicode::general_category::Nl(c) ||
unicode::general_category::No(c);
}
#[doc(
brief = "Convert a char to the corresponding digit. \
Safety note: This function fails if `c` is not a valid char",
return = "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."
)]
pure fn to_digit(c: char) -> u8 unsafe {
alt maybe_digit(c) {
option::some(x) { x }
option::none { fail; }
}
}
#[doc(
brief = "Convert a char to the corresponding digit. Returns none when \
character is not a valid hexadecimal digit."
)]
pure fn maybe_digit(c: char) -> option<u8> {
alt c {
'0' to '9' { option::some(c as u8 - ('0' as u8)) }
'a' to 'z' { option::some(c as u8 + 10u8 - ('a' as u8)) }
'A' to 'Z' { option::some(c as u8 + 10u8 - ('A' as u8)) }
_ { option::none }
}
}
/*
FIXME: works only on ASCII
*/
#[doc(
brief = "Convert a char to the corresponding lower case."
)]
pure fn to_lower(c: char) -> char {
alt c {
'A' to 'Z' { ((c as u8) + 32u8) as char }
_ { c }
}
}
/*
FIXME: works only on ASCII
*/
#[doc(
brief = "Convert a char to the corresponding upper case."
)]
pure fn to_upper(c: char) -> char {
alt c {
'a' to 'z' { ((c as u8) - 32u8) as char }
_ { c }
}
}
#[doc(
brief = "Compare two chars.",
return = "-1 if a<b, 0 if a==b, +1 if a>b"
)]
pure fn cmp(a: char, b: char) -> int {
ret if b > a { -1 }
else if b < a { 1 }
else { 0 }
}
#[test]
fn test_is_lowercase() {
assert is_lowercase('a');
assert is_lowercase('ö');
assert is_lowercase('ß');
assert !is_lowercase('Ü');
assert !is_lowercase('P');
}
#[test]
fn test_is_uppercase() {
assert !is_uppercase('h');
assert !is_uppercase('ä');
assert !is_uppercase('ß');
assert is_uppercase('Ö');
assert is_uppercase('T');
}
#[test]
fn test_is_whitespace() {
assert is_whitespace(' ');
assert is_whitespace('\u2007');
assert is_whitespace('\t');
assert is_whitespace('\n');
assert !is_whitespace('a');
assert !is_whitespace('_');
assert !is_whitespace('\u0000');
}
#[test]
fn test_to_digit() {
assert (to_digit('0') == 0u8);
assert (to_digit('1') == 1u8);
assert (to_digit('2') == 2u8);
assert (to_digit('9') == 9u8);
assert (to_digit('a') == 10u8);
assert (to_digit('A') == 10u8);
assert (to_digit('b') == 11u8);
assert (to_digit('B') == 11u8);
assert (to_digit('z') == 35u8);
assert (to_digit('Z') == 35u8);
}
#[test]
#[should_fail]
#[ignore(cfg(target_os = "win32"))]
fn test_to_digit_fail_1() {
to_digit(' ');
}
#[test]
#[should_fail]
#[ignore(cfg(target_os = "win32"))]
fn test_to_digit_fail_2() {
to_digit('$');
}
#[test]
fn test_to_lower() {
assert (to_lower('H') == 'h');
assert (to_lower('e') == 'e');
//assert (to_lower('Ö') == 'ö');
assert (to_lower('ß') == 'ß');
}
#[test]
fn test_to_upper() {
assert (to_upper('l') == 'L');
assert (to_upper('Q') == 'Q');
//assert (to_upper('ü') == 'Ü');
assert (to_upper('ß') == 'ß');
}
#[test]
fn test_is_ascii() unsafe {
assert str::all("banana", char::is_ascii);
assert ! str::all("ประเทศไทย中华Việt Nam", char::is_ascii);
}
#[test]
fn test_is_digit() {
assert is_digit('2');
assert is_digit('7');
assert ! is_digit('c');
assert ! is_digit('i');
assert ! is_digit('z');
assert ! is_digit('Q');
}