Enum mime::Attr
[−]
[src]
pub enum Attr { Charset, Boundary, Q, Ext(String), }
Variants
Charset
Boundary
Q
Ext(String)
Methods
impl Attr
[src]
Methods from Deref<Target=str>
fn len(&self) -> usize
1.0.0
Returns the length of self
.
This length is in bytes, not char
s or graphemes. In other words,
it may not be what a human considers the length of the string.
Examples
Basic usage:
let len = "foo".len(); assert_eq!(3, len); let len = "ƒoo".len(); // fancy f! assert_eq!(4, len);
fn is_empty(&self) -> bool
1.0.0
Returns true if this slice has a length of zero bytes.
Examples
Basic usage:
let s = ""; assert!(s.is_empty()); let s = "not empty"; assert!(!s.is_empty());
fn is_char_boundary(&self, index: usize) -> bool
1.9.0
Checks that index
-th byte lies at the start and/or end of a
UTF-8 code point sequence.
The start and end of the string (when index == self.len()
) are
considered to be
boundaries.
Returns false
if index
is greater than self.len()
.
Examples
let s = "Löwe 老虎 Léopard"; assert!(s.is_char_boundary(0)); // start of `老` assert!(s.is_char_boundary(6)); assert!(s.is_char_boundary(s.len())); // second byte of `ö` assert!(!s.is_char_boundary(2)); // third byte of `老` assert!(!s.is_char_boundary(8));
fn as_bytes(&self) -> &[u8]
1.0.0
Converts a string slice to a byte slice.
Examples
Basic usage:
let bytes = "bors".as_bytes(); assert_eq!(b"bors", bytes);
fn as_ptr(&self) -> *const u8
1.0.0
Converts a string slice to a raw pointer.
As string slices are a slice of bytes, the raw pointer points to a
u8
. This pointer will be pointing to the first byte of the string
slice.
Examples
Basic usage:
let s = "Hello"; let ptr = s.as_ptr();
unsafe fn slice_unchecked(&self, begin: usize, end: usize) -> &str
1.0.0
Creates a string slice from another string slice, bypassing safety checks.
This new slice goes from begin
to end
, including begin
but
excluding end
.
To get a mutable string slice instead, see the
slice_mut_unchecked()
method.
Safety
Callers of this function are responsible that three preconditions are satisfied:
begin
must come beforeend
.begin
andend
must be byte positions within the string slice.begin
andend
must lie on UTF-8 sequence boundaries.
Examples
Basic usage:
let s = "Löwe 老虎 Léopard"; unsafe { assert_eq!("Löwe 老虎 Léopard", s.slice_unchecked(0, 21)); } let s = "Hello, world!"; unsafe { assert_eq!("world", s.slice_unchecked(7, 12)); }
unsafe fn slice_mut_unchecked(&mut self, begin: usize, end: usize) -> &mut str
1.5.0
Creates a string slice from another string slice, bypassing safety checks.
This new slice goes from begin
to end
, including begin
but
excluding end
.
To get an immutable string slice instead, see the
slice_unchecked()
method.
Safety
Callers of this function are responsible that three preconditions are satisfied:
begin
must come beforeend
.begin
andend
must be byte positions within the string slice.begin
andend
must lie on UTF-8 sequence boundaries.
fn split_at(&self, mid: usize) -> (&str, &str)
1.4.0
Divide one string slice into two at an index.
The argument, mid
, should be a byte offset from the start of the
string. It must also be on the boundary of a UTF-8 code point.
The two slices returned go from the start of the string slice to mid
,
and from mid
to the end of the string slice.
To get mutable string slices instead, see the split_at_mut()
method.
Panics
Panics if mid
is not on a UTF-8 code point boundary, or if it is
beyond the last code point of the string slice.
Examples
Basic usage:
let s = "Per Martin-Löf"; let (first, last) = s.split_at(3); assert_eq!("Per", first); assert_eq!(" Martin-Löf", last);
fn split_at_mut(&mut self, mid: usize) -> (&mut str, &mut str)
1.4.0
Divide one mutable string slice into two at an index.
The argument, mid
, should be a byte offset from the start of the
string. It must also be on the boundary of a UTF-8 code point.
The two slices returned go from the start of the string slice to mid
,
and from mid
to the end of the string slice.
To get immutable string slices instead, see the split_at()
method.
Panics
Panics if mid
is not on a UTF-8 code point boundary, or if it is
beyond the last code point of the string slice.
Examples
Basic usage:
let mut s = "Per Martin-Löf".to_string(); let (first, last) = s.split_at_mut(3); assert_eq!("Per", first); assert_eq!(" Martin-Löf", last);
fn chars(&self) -> Chars
1.0.0
Returns an iterator over the char
s of a string slice.
As a string slice consists of valid UTF-8, we can iterate through a
string slice by char
. This method returns such an iterator.
It's important to remember that char
represents a Unicode Scalar
Value, and may not match your idea of what a 'character' is. Iteration
over grapheme clusters may be what you actually want.
Examples
Basic usage:
let word = "goodbye"; let count = word.chars().count(); assert_eq!(7, count); let mut chars = word.chars(); assert_eq!(Some('g'), chars.next()); assert_eq!(Some('o'), chars.next()); assert_eq!(Some('o'), chars.next()); assert_eq!(Some('d'), chars.next()); assert_eq!(Some('b'), chars.next()); assert_eq!(Some('y'), chars.next()); assert_eq!(Some('e'), chars.next()); assert_eq!(None, chars.next());
Remember, char
s may not match your human intuition about characters:
let y = "y̆"; let mut chars = y.chars(); assert_eq!(Some('y'), chars.next()); // not 'y̆' assert_eq!(Some('\u{0306}'), chars.next()); assert_eq!(None, chars.next());
fn char_indices(&self) -> CharIndices
1.0.0
Returns an iterator over the char
s of a string slice, and their
positions.
As a string slice consists of valid UTF-8, we can iterate through a
string slice by char
. This method returns an iterator of both
these char
s, as well as their byte positions.
The iterator yields tuples. The position is first, the char
is
second.
Examples
Basic usage:
let word = "goodbye"; let count = word.char_indices().count(); assert_eq!(7, count); let mut char_indices = word.char_indices(); assert_eq!(Some((0, 'g')), char_indices.next()); assert_eq!(Some((1, 'o')), char_indices.next()); assert_eq!(Some((2, 'o')), char_indices.next()); assert_eq!(Some((3, 'd')), char_indices.next()); assert_eq!(Some((4, 'b')), char_indices.next()); assert_eq!(Some((5, 'y')), char_indices.next()); assert_eq!(Some((6, 'e')), char_indices.next()); assert_eq!(None, char_indices.next());
Remember, char
s may not match your human intuition about characters:
let y = "y̆"; let mut char_indices = y.char_indices(); assert_eq!(Some((0, 'y')), char_indices.next()); // not (0, 'y̆') assert_eq!(Some((1, '\u{0306}')), char_indices.next()); assert_eq!(None, char_indices.next());
fn bytes(&self) -> Bytes
1.0.0
An iterator over the bytes of a string slice.
As a string slice consists of a sequence of bytes, we can iterate through a string slice by byte. This method returns such an iterator.
Examples
Basic usage:
let mut bytes = "bors".bytes(); assert_eq!(Some(b'b'), bytes.next()); assert_eq!(Some(b'o'), bytes.next()); assert_eq!(Some(b'r'), bytes.next()); assert_eq!(Some(b's'), bytes.next()); assert_eq!(None, bytes.next());
fn split_whitespace(&self) -> SplitWhitespace
1.1.0
Split a string slice by whitespace.
The iterator returned will return string slices that are sub-slices of the original string slice, separated by any amount of whitespace.
'Whitespace' is defined according to the terms of the Unicode Derived
Core Property White_Space
.
Examples
Basic usage:
let mut iter = "A few words".split_whitespace(); assert_eq!(Some("A"), iter.next()); assert_eq!(Some("few"), iter.next()); assert_eq!(Some("words"), iter.next()); assert_eq!(None, iter.next());
All kinds of whitespace are considered:
let mut iter = " Mary had\ta\u{2009}little \n\t lamb".split_whitespace(); assert_eq!(Some("Mary"), iter.next()); assert_eq!(Some("had"), iter.next()); assert_eq!(Some("a"), iter.next()); assert_eq!(Some("little"), iter.next()); assert_eq!(Some("lamb"), iter.next()); assert_eq!(None, iter.next());
fn lines(&self) -> Lines
1.0.0
An iterator over the lines of a string, as string slices.
Lines are ended with either a newline (\n
) or a carriage return with
a line feed (\r\n
).
The final line ending is optional.
Examples
Basic usage:
let text = "foo\r\nbar\n\nbaz\n"; let mut lines = text.lines(); assert_eq!(Some("foo"), lines.next()); assert_eq!(Some("bar"), lines.next()); assert_eq!(Some(""), lines.next()); assert_eq!(Some("baz"), lines.next()); assert_eq!(None, lines.next());
The final line ending isn't required:
let text = "foo\nbar\n\r\nbaz"; let mut lines = text.lines(); assert_eq!(Some("foo"), lines.next()); assert_eq!(Some("bar"), lines.next()); assert_eq!(Some(""), lines.next()); assert_eq!(Some("baz"), lines.next()); assert_eq!(None, lines.next());
fn lines_any(&self) -> LinesAny
1.0.0
: use lines() instead now
An iterator over the lines of a string.
fn encode_utf16(&self) -> EncodeUtf16
1.8.0
Returns an iterator of u16
over the string encoded as UTF-16.
fn contains<'a, P>(&'a self, pat: P) -> bool where P: Pattern<'a>
1.0.0
Returns true
if the given pattern matches a sub-slice of
this string slice.
Returns false
if it does not.
Examples
Basic usage:
let bananas = "bananas"; assert!(bananas.contains("nana")); assert!(!bananas.contains("apples"));
fn starts_with<'a, P>(&'a self, pat: P) -> bool where P: Pattern<'a>
1.0.0
Returns true
if the given pattern matches a prefix of this
string slice.
Returns false
if it does not.
Examples
Basic usage:
let bananas = "bananas"; assert!(bananas.starts_with("bana")); assert!(!bananas.starts_with("nana"));
fn ends_with<'a, P>(&'a self, pat: P) -> bool where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.0.0
Returns true
if the given pattern matches a suffix of this
string slice.
Returns false
if it does not.
Examples
Basic usage:
let bananas = "bananas"; assert!(bananas.ends_with("anas")); assert!(!bananas.ends_with("nana"));
fn find<'a, P>(&'a self, pat: P) -> Option<usize> where P: Pattern<'a>
1.0.0
Returns the byte index of the first character of this string slice that matches the pattern.
Returns None
if the pattern doesn't match.
The pattern can be a &str
, char
, or a closure that determines if
a character matches.
Examples
Simple patterns:
let s = "Löwe 老虎 Léopard"; assert_eq!(s.find('L'), Some(0)); assert_eq!(s.find('é'), Some(14)); assert_eq!(s.find("Léopard"), Some(13));
More complex patterns with closures:
let s = "Löwe 老虎 Léopard"; assert_eq!(s.find(char::is_whitespace), Some(5)); assert_eq!(s.find(char::is_lowercase), Some(1));
Not finding the pattern:
let s = "Löwe 老虎 Léopard"; let x: &[_] = &['1', '2']; assert_eq!(s.find(x), None);
fn rfind<'a, P>(&'a self, pat: P) -> Option<usize> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.0.0
Returns the byte index of the last character of this string slice that matches the pattern.
Returns None
if the pattern doesn't match.
The pattern can be a &str
, char
, or a closure that determines if
a character matches.
Examples
Simple patterns:
let s = "Löwe 老虎 Léopard"; assert_eq!(s.rfind('L'), Some(13)); assert_eq!(s.rfind('é'), Some(14));
More complex patterns with closures:
let s = "Löwe 老虎 Léopard"; assert_eq!(s.rfind(char::is_whitespace), Some(12)); assert_eq!(s.rfind(char::is_lowercase), Some(20));
Not finding the pattern:
let s = "Löwe 老虎 Léopard"; let x: &[_] = &['1', '2']; assert_eq!(s.rfind(x), None);
fn split<'a, P>(&'a self, pat: P) -> Split<'a, P> where P: Pattern<'a>
1.0.0
An iterator over substrings of this string slice, separated by characters matched by a pattern.
The pattern can be a &str
, char
, or a closure that determines the
split.
Iterator behavior
The returned iterator will be a DoubleEndedIterator
if the pattern
allows a reverse search and forward/reverse search yields the same
elements. This is true for, eg, char
but not for &str
.
If the pattern allows a reverse search but its results might differ
from a forward search, the rsplit()
method can be used.
Examples
Simple patterns:
let v: Vec<&str> = "Mary had a little lamb".split(' ').collect(); assert_eq!(v, ["Mary", "had", "a", "little", "lamb"]); let v: Vec<&str> = "".split('X').collect(); assert_eq!(v, [""]); let v: Vec<&str> = "lionXXtigerXleopard".split('X').collect(); assert_eq!(v, ["lion", "", "tiger", "leopard"]); let v: Vec<&str> = "lion::tiger::leopard".split("::").collect(); assert_eq!(v, ["lion", "tiger", "leopard"]); let v: Vec<&str> = "abc1def2ghi".split(char::is_numeric).collect(); assert_eq!(v, ["abc", "def", "ghi"]); let v: Vec<&str> = "lionXtigerXleopard".split(char::is_uppercase).collect(); assert_eq!(v, ["lion", "tiger", "leopard"]);
A more complex pattern, using a closure:
let v: Vec<&str> = "abc1defXghi".split(|c| c == '1' || c == 'X').collect(); assert_eq!(v, ["abc", "def", "ghi"]);
If a string contains multiple contiguous separators, you will end up with empty strings in the output:
let x = "||||a||b|c".to_string(); let d: Vec<_> = x.split('|').collect(); assert_eq!(d, &["", "", "", "", "a", "", "b", "c"]);
Contiguous separators are separated by the empty string.
let x = "(///)".to_string(); let d: Vec<_> = x.split('/').collect();; assert_eq!(d, &["(", "", "", ")"]);
Separators at the start or end of a string are neighbored by empty strings.
let d: Vec<_> = "010".split("0").collect(); assert_eq!(d, &["", "1", ""]);
When the empty string is used as a separator, it separates every character in the string, along with the beginning and end of the string.
let f: Vec<_> = "rust".split("").collect(); assert_eq!(f, &["", "r", "u", "s", "t", ""]);
Contiguous separators can lead to possibly surprising behavior when whitespace is used as the separator. This code is correct:
let x = " a b c".to_string(); let d: Vec<_> = x.split(' ').collect(); assert_eq!(d, &["", "", "", "", "a", "", "b", "c"]);
It does not give you:
assert_eq!(d, &["a", "b", "c"]);
Use split_whitespace()
for this behavior.
fn rsplit<'a, P>(&'a self, pat: P) -> RSplit<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.0.0
An iterator over substrings of the given string slice, separated by characters matched by a pattern and yielded in reverse order.
The pattern can be a &str
, char
, or a closure that determines the
split.
Iterator behavior
The returned iterator requires that the pattern supports a reverse
search, and it will be a DoubleEndedIterator
if a forward/reverse
search yields the same elements.
For iterating from the front, the split()
method can be used.
Examples
Simple patterns:
let v: Vec<&str> = "Mary had a little lamb".rsplit(' ').collect(); assert_eq!(v, ["lamb", "little", "a", "had", "Mary"]); let v: Vec<&str> = "".rsplit('X').collect(); assert_eq!(v, [""]); let v: Vec<&str> = "lionXXtigerXleopard".rsplit('X').collect(); assert_eq!(v, ["leopard", "tiger", "", "lion"]); let v: Vec<&str> = "lion::tiger::leopard".rsplit("::").collect(); assert_eq!(v, ["leopard", "tiger", "lion"]);
A more complex pattern, using a closure:
let v: Vec<&str> = "abc1defXghi".rsplit(|c| c == '1' || c == 'X').collect(); assert_eq!(v, ["ghi", "def", "abc"]);
fn split_terminator<'a, P>(&'a self, pat: P) -> SplitTerminator<'a, P> where P: Pattern<'a>
1.0.0
An iterator over substrings of the given string slice, separated by characters matched by a pattern.
The pattern can be a &str
, char
, or a closure that determines the
split.
Equivalent to split()
, except that the trailing substring
is skipped if empty.
This method can be used for string data that is terminated, rather than separated by a pattern.
Iterator behavior
The returned iterator will be a DoubleEndedIterator
if the pattern
allows a reverse search and forward/reverse search yields the same
elements. This is true for, eg, char
but not for &str
.
If the pattern allows a reverse search but its results might differ
from a forward search, the rsplit_terminator()
method can be used.
Examples
Basic usage:
let v: Vec<&str> = "A.B.".split_terminator('.').collect(); assert_eq!(v, ["A", "B"]); let v: Vec<&str> = "A..B..".split_terminator(".").collect(); assert_eq!(v, ["A", "", "B", ""]);
fn rsplit_terminator<'a, P>(&'a self, pat: P) -> RSplitTerminator<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.0.0
An iterator over substrings of self
, separated by characters
matched by a pattern and yielded in reverse order.
The pattern can be a simple &str
, char
, or a closure that
determines the split.
Additional libraries might provide more complex patterns like
regular expressions.
Equivalent to split()
, except that the trailing substring is
skipped if empty.
This method can be used for string data that is terminated, rather than separated by a pattern.
Iterator behavior
The returned iterator requires that the pattern supports a reverse search, and it will be double ended if a forward/reverse search yields the same elements.
For iterating from the front, the split_terminator()
method can be
used.
Examples
let v: Vec<&str> = "A.B.".rsplit_terminator('.').collect(); assert_eq!(v, ["B", "A"]); let v: Vec<&str> = "A..B..".rsplit_terminator(".").collect(); assert_eq!(v, ["", "B", "", "A"]);
fn splitn<'a, P>(&'a self, count: usize, pat: P) -> SplitN<'a, P> where P: Pattern<'a>
1.0.0
An iterator over substrings of the given string slice, separated by a
pattern, restricted to returning at most count
items.
The last element returned, if any, will contain the remainder of the string slice.
The pattern can be a &str
, char
, or a closure that determines the
split.
Iterator behavior
The returned iterator will not be double ended, because it is not efficient to support.
If the pattern allows a reverse search, the rsplitn()
method can be
used.
Examples
Simple patterns:
let v: Vec<&str> = "Mary had a little lambda".splitn(3, ' ').collect(); assert_eq!(v, ["Mary", "had", "a little lambda"]); let v: Vec<&str> = "lionXXtigerXleopard".splitn(3, "X").collect(); assert_eq!(v, ["lion", "", "tigerXleopard"]); let v: Vec<&str> = "abcXdef".splitn(1, 'X').collect(); assert_eq!(v, ["abcXdef"]); let v: Vec<&str> = "".splitn(1, 'X').collect(); assert_eq!(v, [""]);
A more complex pattern, using a closure:
let v: Vec<&str> = "abc1defXghi".splitn(2, |c| c == '1' || c == 'X').collect(); assert_eq!(v, ["abc", "defXghi"]);
fn rsplitn<'a, P>(&'a self, count: usize, pat: P) -> RSplitN<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.0.0
An iterator over substrings of this string slice, separated by a
pattern, starting from the end of the string, restricted to returning
at most count
items.
The last element returned, if any, will contain the remainder of the string slice.
The pattern can be a &str
, char
, or a closure that
determines the split.
Iterator behavior
The returned iterator will not be double ended, because it is not efficient to support.
For splitting from the front, the splitn()
method can be used.
Examples
Simple patterns:
let v: Vec<&str> = "Mary had a little lamb".rsplitn(3, ' ').collect(); assert_eq!(v, ["lamb", "little", "Mary had a"]); let v: Vec<&str> = "lionXXtigerXleopard".rsplitn(3, 'X').collect(); assert_eq!(v, ["leopard", "tiger", "lionX"]); let v: Vec<&str> = "lion::tiger::leopard".rsplitn(2, "::").collect(); assert_eq!(v, ["leopard", "lion::tiger"]);
A more complex pattern, using a closure:
let v: Vec<&str> = "abc1defXghi".rsplitn(2, |c| c == '1' || c == 'X').collect(); assert_eq!(v, ["ghi", "abc1def"]);
fn matches<'a, P>(&'a self, pat: P) -> Matches<'a, P> where P: Pattern<'a>
1.2.0
An iterator over the matches of a pattern within the given string slice.
The pattern can be a &str
, char
, or a closure that
determines if a character matches.
Iterator behavior
The returned iterator will be a DoubleEndedIterator
if the pattern
allows a reverse search and forward/reverse search yields the same
elements. This is true for, eg, char
but not for &str
.
If the pattern allows a reverse search but its results might differ
from a forward search, the rmatches()
method can be used.
Examples
Basic usage:
let v: Vec<&str> = "abcXXXabcYYYabc".matches("abc").collect(); assert_eq!(v, ["abc", "abc", "abc"]); let v: Vec<&str> = "1abc2abc3".matches(char::is_numeric).collect(); assert_eq!(v, ["1", "2", "3"]);
fn rmatches<'a, P>(&'a self, pat: P) -> RMatches<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.2.0
An iterator over the matches of a pattern within this string slice, yielded in reverse order.
The pattern can be a &str
, char
, or a closure that determines if
a character matches.
Iterator behavior
The returned iterator requires that the pattern supports a reverse
search, and it will be a DoubleEndedIterator
if a forward/reverse
search yields the same elements.
For iterating from the front, the matches()
method can be used.
Examples
Basic usage:
let v: Vec<&str> = "abcXXXabcYYYabc".rmatches("abc").collect(); assert_eq!(v, ["abc", "abc", "abc"]); let v: Vec<&str> = "1abc2abc3".rmatches(char::is_numeric).collect(); assert_eq!(v, ["3", "2", "1"]);
fn match_indices<'a, P>(&'a self, pat: P) -> MatchIndices<'a, P> where P: Pattern<'a>
1.5.0
An iterator over the disjoint matches of a pattern within this string slice as well as the index that the match starts at.
For matches of pat
within self
that overlap, only the indices
corresponding to the first match are returned.
The pattern can be a &str
, char
, or a closure that determines
if a character matches.
Iterator behavior
The returned iterator will be a DoubleEndedIterator
if the pattern
allows a reverse search and forward/reverse search yields the same
elements. This is true for, eg, char
but not for &str
.
If the pattern allows a reverse search but its results might differ
from a forward search, the rmatch_indices()
method can be used.
Examples
Basic usage:
let v: Vec<_> = "abcXXXabcYYYabc".match_indices("abc").collect(); assert_eq!(v, [(0, "abc"), (6, "abc"), (12, "abc")]); let v: Vec<_> = "1abcabc2".match_indices("abc").collect(); assert_eq!(v, [(1, "abc"), (4, "abc")]); let v: Vec<_> = "ababa".match_indices("aba").collect(); assert_eq!(v, [(0, "aba")]); // only the first `aba`
fn rmatch_indices<'a, P>(&'a self, pat: P) -> RMatchIndices<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.5.0
An iterator over the disjoint matches of a pattern within self
,
yielded in reverse order along with the index of the match.
For matches of pat
within self
that overlap, only the indices
corresponding to the last match are returned.
The pattern can be a &str
, char
, or a closure that determines if a
character matches.
Iterator behavior
The returned iterator requires that the pattern supports a reverse
search, and it will be a DoubleEndedIterator
if a forward/reverse
search yields the same elements.
For iterating from the front, the match_indices()
method can be used.
Examples
Basic usage:
let v: Vec<_> = "abcXXXabcYYYabc".rmatch_indices("abc").collect(); assert_eq!(v, [(12, "abc"), (6, "abc"), (0, "abc")]); let v: Vec<_> = "1abcabc2".rmatch_indices("abc").collect(); assert_eq!(v, [(4, "abc"), (1, "abc")]); let v: Vec<_> = "ababa".rmatch_indices("aba").collect(); assert_eq!(v, [(2, "aba")]); // only the last `aba`
fn trim(&self) -> &str
1.0.0
Returns a string slice with leading and trailing whitespace removed.
'Whitespace' is defined according to the terms of the Unicode Derived
Core Property White_Space
.
Examples
Basic usage:
let s = " Hello\tworld\t"; assert_eq!("Hello\tworld", s.trim());
fn trim_left(&self) -> &str
1.0.0
Returns a string slice with leading whitespace removed.
'Whitespace' is defined according to the terms of the Unicode Derived
Core Property White_Space
.
Text directionality
A string is a sequence of bytes. 'Left' in this context means the first position of that byte string; for a language like Arabic or Hebrew which are 'right to left' rather than 'left to right', this will be the right side, not the left.
Examples
Basic usage:
let s = " Hello\tworld\t"; assert_eq!("Hello\tworld\t", s.trim_left());
Directionality:
let s = " English"; assert!(Some('E') == s.trim_left().chars().next()); let s = " עברית"; assert!(Some('ע') == s.trim_left().chars().next());
fn trim_right(&self) -> &str
1.0.0
Returns a string slice with trailing whitespace removed.
'Whitespace' is defined according to the terms of the Unicode Derived
Core Property White_Space
.
Text directionality
A string is a sequence of bytes. 'Right' in this context means the last position of that byte string; for a language like Arabic or Hebrew which are 'right to left' rather than 'left to right', this will be the left side, not the right.
Examples
Basic usage:
let s = " Hello\tworld\t"; assert_eq!(" Hello\tworld", s.trim_right());
Directionality:
let s = "English "; assert!(Some('h') == s.trim_right().chars().rev().next()); let s = "עברית "; assert!(Some('ת') == s.trim_right().chars().rev().next());
fn trim_matches<'a, P>(&'a self, pat: P) -> &'a str where P: Pattern<'a>, P::Searcher: DoubleEndedSearcher<'a>
1.0.0
Returns a string slice with all prefixes and suffixes that match a pattern repeatedly removed.
The pattern can be a char
or a closure that determines if a
character matches.
Examples
Simple patterns:
assert_eq!("11foo1bar11".trim_matches('1'), "foo1bar"); assert_eq!("123foo1bar123".trim_matches(char::is_numeric), "foo1bar"); let x: &[_] = &['1', '2']; assert_eq!("12foo1bar12".trim_matches(x), "foo1bar");
A more complex pattern, using a closure:
assert_eq!("1foo1barXX".trim_matches(|c| c == '1' || c == 'X'), "foo1bar");
fn trim_left_matches<'a, P>(&'a self, pat: P) -> &'a str where P: Pattern<'a>
1.0.0
Returns a string slice with all prefixes that match a pattern repeatedly removed.
The pattern can be a &str
, char
, or a closure that determines if
a character matches.
Text directionality
A string is a sequence of bytes. 'Left' in this context means the first position of that byte string; for a language like Arabic or Hebrew which are 'right to left' rather than 'left to right', this will be the right side, not the left.
Examples
Basic usage:
assert_eq!("11foo1bar11".trim_left_matches('1'), "foo1bar11"); assert_eq!("123foo1bar123".trim_left_matches(char::is_numeric), "foo1bar123"); let x: &[_] = &['1', '2']; assert_eq!("12foo1bar12".trim_left_matches(x), "foo1bar12");
fn trim_right_matches<'a, P>(&'a self, pat: P) -> &'a str where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>
1.0.0
Returns a string slice with all suffixes that match a pattern repeatedly removed.
The pattern can be a &str
, char
, or a closure that
determines if a character matches.
Text directionality
A string is a sequence of bytes. 'Right' in this context means the last position of that byte string; for a language like Arabic or Hebrew which are 'right to left' rather than 'left to right', this will be the left side, not the right.
Examples
Simple patterns:
assert_eq!("11foo1bar11".trim_right_matches('1'), "11foo1bar"); assert_eq!("123foo1bar123".trim_right_matches(char::is_numeric), "123foo1bar"); let x: &[_] = &['1', '2']; assert_eq!("12foo1bar12".trim_right_matches(x), "12foo1bar");
A more complex pattern, using a closure:
assert_eq!("1fooX".trim_left_matches(|c| c == '1' || c == 'X'), "fooX");
fn parse<F>(&self) -> Result<F, F::Err> where F: FromStr
1.0.0
Parses this string slice into another type.
Because parse()
is so general, it can cause problems with type
inference. As such, parse()
is one of the few times you'll see
the syntax affectionately known as the 'turbofish': ::<>
. This
helps the inference algorithm understand specifically which type
you're trying to parse into.
parse()
can parse any type that implements the FromStr
trait.
Errors
Will return Err
if it's not possible to parse this string slice into
the desired type.
Example
Basic usage
let four: u32 = "4".parse().unwrap(); assert_eq!(4, four);
Using the 'turbofish' instead of annotating four
:
let four = "4".parse::<u32>(); assert_eq!(Ok(4), four);
Failing to parse:
let nope = "j".parse::<u32>(); assert!(nope.is_err());
fn replace<'a, P>(&'a self, from: P, to: &str) -> String where P: Pattern<'a>
1.0.0
Replaces all matches of a pattern with another string.
replace
creates a new String
, and copies the data from this string slice into it.
While doing so, it attempts to find matches of a pattern. If it finds any, it
replaces them with the replacement string slice.
Examples
Basic usage:
let s = "this is old"; assert_eq!("this is new", s.replace("old", "new"));
When the pattern doesn't match:
let s = "this is old"; assert_eq!(s, s.replace("cookie monster", "little lamb"));
fn to_lowercase(&self) -> String
1.2.0
Returns the lowercase equivalent of this string slice, as a new String
.
'Lowercase' is defined according to the terms of the Unicode Derived Core Property
Lowercase
.
Examples
Basic usage:
let s = "HELLO"; assert_eq!("hello", s.to_lowercase());
A tricky example, with sigma:
let sigma = "Σ"; assert_eq!("σ", sigma.to_lowercase()); // but at the end of a word, it's ς, not σ: let odysseus = "ὈΔΥΣΣΕΎΣ"; assert_eq!("ὀδυσσεύς", odysseus.to_lowercase());
Languages without case are not changed:
let new_year = "农历新年"; assert_eq!(new_year, new_year.to_lowercase());
fn to_uppercase(&self) -> String
1.2.0
Returns the uppercase equivalent of this string slice, as a new String
.
'Uppercase' is defined according to the terms of the Unicode Derived Core Property
Uppercase
.
Examples
Basic usage:
let s = "hello"; assert_eq!("HELLO", s.to_uppercase());
Scripts without case are not changed:
let new_year = "农历新年"; assert_eq!(new_year, new_year.to_uppercase());
fn escape_debug(&self) -> String
str_escape
): return type may change to be an iterator
Escapes each char in s
with char::escape_debug
.
fn escape_default(&self) -> String
str_escape
): return type may change to be an iterator
Escapes each char in s
with char::escape_default
.
fn escape_unicode(&self) -> String
str_escape
): return type may change to be an iterator
Escapes each char in s
with char::escape_unicode
.
fn into_string(self: Box<str>) -> String
1.4.0
Trait Implementations
impl Eq for Attr
[src]
impl Hash for Attr
[src]
fn hash<__H: Hasher>(&self, __arg_0: &mut __H)
Feeds this value into the state given, updating the hasher as necessary.
fn hash_slice<H>(data: &[Self], state: &mut H) where H: Hasher
1.3.0
Feeds a slice of this type into the state provided.
impl Debug for Attr
[src]
impl Clone for Attr
[src]
fn clone(&self) -> Attr
Returns a copy of the value. Read more
fn clone_from(&mut self, source: &Self)
1.0.0
Performs copy-assignment from source
. Read more
impl Deref for Attr
[src]
type Target = str
The resulting type after dereferencing
fn deref(&self) -> &str
The method called to dereference a value
impl PartialEq for Attr
[src]
fn eq(&self, other: &Attr) -> bool
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Rhs) -> bool
1.0.0
This method tests for !=
.
impl PartialEq<String> for Attr
[src]
fn eq(&self, other: &String) -> bool
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Rhs) -> bool
1.0.0
This method tests for !=
.
impl PartialEq<str> for Attr
[src]
fn eq(&self, other: &str) -> bool
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Rhs) -> bool
1.0.0
This method tests for !=
.
impl<'a> PartialEq<&'a str> for Attr
[src]
fn eq(&self, other: &&'a str) -> bool
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Rhs) -> bool
1.0.0
This method tests for !=
.