diff options
Diffstat (limited to '')
| -rw-r--r-- | library/core/src/char/methods.rs | 62 |
1 files changed, 58 insertions, 4 deletions
diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs index eae567cad..bb8359936 100644 --- a/library/core/src/char/methods.rs +++ b/library/core/src/char/methods.rs @@ -597,9 +597,14 @@ impl char { /// Returns the number of 16-bit code units this `char` would need if /// encoded in UTF-16. /// + /// That number of code units is always either 1 or 2, for unicode scalar values in + /// the [basic multilingual plane] or [supplementary planes] respectively. + /// /// See the documentation for [`len_utf8()`] for more explanation of this /// concept. This function is a mirror, but for UTF-16 instead of UTF-8. /// + /// [basic multilingual plane]: http://www.unicode.org/glossary/#basic_multilingual_plane + /// [supplementary planes]: http://www.unicode.org/glossary/#supplementary_planes /// [`len_utf8()`]: #method.len_utf8 /// /// # Examples @@ -746,10 +751,19 @@ impl char { /// assert!(!'中'.is_lowercase()); /// assert!(!' '.is_lowercase()); /// ``` + /// + /// In a const context: + /// + /// ``` + /// #![feature(const_unicode_case_lookup)] + /// const CAPITAL_DELTA_IS_LOWERCASE: bool = 'Δ'.is_lowercase(); + /// assert!(!CAPITAL_DELTA_IS_LOWERCASE); + /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] + #[rustc_const_unstable(feature = "const_unicode_case_lookup", issue = "101400")] #[inline] - pub fn is_lowercase(self) -> bool { + pub const fn is_lowercase(self) -> bool { match self { 'a'..='z' => true, c => c > '\x7f' && unicode::Lowercase(c), @@ -779,10 +793,19 @@ impl char { /// assert!(!'中'.is_uppercase()); /// assert!(!' '.is_uppercase()); /// ``` + /// + /// In a const context: + /// + /// ``` + /// #![feature(const_unicode_case_lookup)] + /// const CAPITAL_DELTA_IS_UPPERCASE: bool = 'Δ'.is_uppercase(); + /// assert!(CAPITAL_DELTA_IS_UPPERCASE); + /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] + #[rustc_const_unstable(feature = "const_unicode_case_lookup", issue = "101400")] #[inline] - pub fn is_uppercase(self) -> bool { + pub const fn is_uppercase(self) -> bool { match self { 'A'..='Z' => true, c => c > '\x7f' && unicode::Uppercase(c), @@ -892,8 +915,7 @@ impl char { /// /// The general categories for numbers (`Nd` for decimal digits, `Nl` for letter-like numeric /// characters, and `No` for other numeric characters) are specified in the [Unicode Character - /// Database][ucd] [`UnicodeData.txt`]. Note that this means ideographic numbers like '三' - /// are considered alphabetic, not numeric. Please consider to use `is_ascii_digit` or `is_digit`. + /// Database][ucd] [`UnicodeData.txt`]. /// /// This method doesn't cover everything that could be considered a number, e.g. ideographic numbers like '三'. /// If you want everything including characters with overlapping purposes then you might want to use @@ -1427,6 +1449,38 @@ impl char { matches!(*self, '0'..='9') } + /// Checks if the value is an ASCII octal digit: + /// U+0030 '0' ..= U+0037 '7'. + /// + /// # Examples + /// + /// ``` + /// #![feature(is_ascii_octdigit)] + /// + /// let uppercase_a = 'A'; + /// let a = 'a'; + /// let zero = '0'; + /// let seven = '7'; + /// let nine = '9'; + /// let percent = '%'; + /// let lf = '\n'; + /// + /// assert!(!uppercase_a.is_ascii_octdigit()); + /// assert!(!a.is_ascii_octdigit()); + /// assert!(zero.is_ascii_octdigit()); + /// assert!(seven.is_ascii_octdigit()); + /// assert!(!nine.is_ascii_octdigit()); + /// assert!(!percent.is_ascii_octdigit()); + /// assert!(!lf.is_ascii_octdigit()); + /// ``` + #[must_use] + #[unstable(feature = "is_ascii_octdigit", issue = "101288")] + #[rustc_const_unstable(feature = "is_ascii_octdigit", issue = "101288")] + #[inline] + pub const fn is_ascii_octdigit(&self) -> bool { + matches!(*self, '0'..='7') + } + /// Checks if the value is an ASCII hexadecimal digit: /// /// - U+0030 '0' ..= U+0039 '9', or |