String slices.
The str
type, also called a 'string slice', is the most primitive string type. It is usually seen in its borrowed form, &str
. It is also the type of string literals, &'static str
.
Strings slices are always valid UTF-8.
This documentation describes a number of methods and trait implementations on the str
type. For technical reasons, there is additional, separate documentation in the std::str
module as well.
String literals are string slices:
let hello = "Hello, world!"; // with an explicit type annotation let hello: &'static str = "Hello, world!";
They are 'static
because they're stored directly in the final binary, and so will be valid for the 'static
duration.
A &str
is made up of two components: a pointer to some bytes, and a length. You can look at these with the as_ptr
and len
methods:
use std::slice; use std::str; let story = "Once upon a time..."; let ptr = story.as_ptr(); let len = story.len(); // story has nineteen bytes assert_eq!(19, len); // We can re-build a str out of ptr and len. This is all unsafe because // we are responsible for making sure the two components are valid: let s = unsafe { // First, we build a &[u8]... let slice = slice::from_raw_parts(ptr, len); // ... and then convert that slice into a string slice str::from_utf8(slice) }; assert_eq!(s, Ok(story));
Note: This example shows the internals of &str
. unsafe
should not be used to get a string slice under normal circumstances. Use as_slice
instead.
impl str
[src]
Methods for string slices.
fn len(&self) -> usize
[src]
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.
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
[src]
Returns true
if self
has a length of zero bytes.
Basic usage:
let s = ""; assert!(s.is_empty()); let s = "not empty"; assert!(!s.is_empty());
fn is_char_boundary(&self, index: usize) -> bool
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()
.
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]
[src]
Converts a string slice to a byte slice. To convert the byte slice back into a string slice, use the str::from_utf8
function.
Basic usage:
let bytes = "bors".as_bytes(); assert_eq!(b"bors", bytes);
unsafe fn as_bytes_mut(&mut self) -> &mut [u8]
Converts a mutable string slice to a mutable byte slice. To convert the mutable byte slice back into a mutable string slice, use the str::from_utf8_mut
function.
Basic usage:
let mut s = String::from("Hello"); let bytes = unsafe { s.as_bytes_mut() }; assert_eq!(b"Hello", bytes);
Mutability:
let mut s = String::from("🗻∈🌏"); unsafe { let bytes = s.as_bytes_mut(); bytes[0] = 0xF0; bytes[1] = 0x9F; bytes[2] = 0x8D; bytes[3] = 0x94; } assert_eq!("🍔∈🌏", s);
fn as_ptr(&self) -> *const u8
[src]
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.
Basic usage:
let s = "Hello"; let ptr = s.as_ptr();
fn get<I>(&self, i: I) -> Option<&<I as SliceIndex<str>>::Output> where
I: SliceIndex<str>,
Returns a subslice of str
.
This is the non-panicking alternative to indexing the str
. Returns None
whenever equivalent indexing operation would panic.
let v = String::from("🗻∈🌏"); assert_eq!(Some("🗻"), v.get(0..4)); // indices not on UTF-8 sequence boundaries assert!(v.get(1..).is_none()); assert!(v.get(..8).is_none()); // out of bounds assert!(v.get(..42).is_none());
fn get_mut<I>(&mut self, i: I) -> Option<&mut <I as SliceIndex<str>>::Output> where
I: SliceIndex<str>,
Returns a mutable subslice of str
.
This is the non-panicking alternative to indexing the str
. Returns None
whenever equivalent indexing operation would panic.
let mut v = String::from("hello"); // correct length assert!(v.get_mut(0..5).is_some()); // out of bounds assert!(v.get_mut(..42).is_none()); assert_eq!(Some("he"), v.get_mut(0..2).map(|v| &*v)); assert_eq!("hello", v); { let s = v.get_mut(0..2); let s = s.map(|s| { s.make_ascii_uppercase(); &*s }); assert_eq!(Some("HE"), s); } assert_eq!("HEllo", v);
unsafe fn get_unchecked<I>(&self, i: I) -> &<I as SliceIndex<str>>::Output where
I: SliceIndex<str>,
Returns a unchecked subslice of str
.
This is the unchecked alternative to indexing the str
.
Callers of this function are responsible that these preconditions are satisfied:
Failing that, the returned string slice may reference invalid memory or violate the invariants communicated by the str
type.
let v = "🗻∈🌏"; unsafe { assert_eq!("🗻", v.get_unchecked(0..4)); assert_eq!("∈", v.get_unchecked(4..7)); assert_eq!("🌏", v.get_unchecked(7..11)); }
unsafe fn get_unchecked_mut<I>(
&mut self,
i: I
) -> &mut <I as SliceIndex<str>>::Output where
I: SliceIndex<str>,
Returns a mutable, unchecked subslice of str
.
This is the unchecked alternative to indexing the str
.
Callers of this function are responsible that these preconditions are satisfied:
Failing that, the returned string slice may reference invalid memory or violate the invariants communicated by the str
type.
let mut v = String::from("🗻∈🌏"); unsafe { assert_eq!("🗻", v.get_unchecked_mut(0..4)); assert_eq!("∈", v.get_unchecked_mut(4..7)); assert_eq!("🌏", v.get_unchecked_mut(7..11)); }
unsafe fn slice_unchecked(&self, begin: usize, end: usize) -> &str
[src]
Creates a string slice from another string slice, bypassing safety checks.
This is generally not recommended, use with caution! For a safe alternative see str
and Index
.
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.
Callers of this function are responsible that three preconditions are satisfied:
begin
must come before end
.begin
and end
must be byte positions within the string slice.begin
and end
must lie on UTF-8 sequence boundaries.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
Creates a string slice from another string slice, bypassing safety checks. This is generally not recommended, use with caution! For a safe alternative see str
and IndexMut
.
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.
Callers of this function are responsible that three preconditions are satisfied:
begin
must come before end
.begin
and end
must be byte positions within the string slice.begin
and end
must lie on UTF-8 sequence boundaries.fn split_at(&self, mid: usize) -> (&str, &str)
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 if mid
is not on a UTF-8 code point boundary, or if it is beyond the last code point of the string slice.
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)
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 if mid
is not on a UTF-8 code point boundary, or if it is beyond the last code point of the string slice.
Basic usage:
let mut s = "Per Martin-Löf".to_string(); { let (first, last) = s.split_at_mut(3); first.make_ascii_uppercase(); assert_eq!("PER", first); assert_eq!(" Martin-Löf", last); } assert_eq!("PER Martin-Löf", s);
fn chars(&self) -> Chars
[src]
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.
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
[src]
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.
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
[src]
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.
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
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
.
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
[src]
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.
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
[src]
An iterator over the lines of a string.
fn encode_utf16(&self) -> EncodeUtf16
Returns an iterator of u16
over the string encoded as UTF-16.
Basic usage:
let text = "Zażółć gęślą jaźń"; let utf8_len = text.len(); let utf16_len = text.encode_utf16().count(); assert!(utf16_len <= utf8_len);
fn contains<'a, P>(&'a self, pat: P) -> bool where
P: Pattern<'a>,
[src]
Returns true
if the given pattern matches a sub-slice of this string slice.
Returns false
if it does not.
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>,
[src]
Returns true
if the given pattern matches a prefix of this string slice.
Returns false
if it does not.
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
[src]
Returns true
if the given pattern matches a suffix of this string slice.
Returns false
if it does not.
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>,
[src]
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.
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 using point-free style and 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)); assert_eq!(s.find(|c: char| c.is_whitespace() || c.is_lowercase()), Some(1)); assert_eq!(s.find(|c: char| (c < 'o') && (c > 'a')), Some(4));
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
[src]
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.
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>,
[src]
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.
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.
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
[src]
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.
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.
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>,
[src]
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.
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.
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
[src]
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.
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.
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, n: usize, pat: P) -> SplitN<'a, P> where
P: Pattern<'a>,
[src]
An iterator over substrings of the given string slice, separated by a pattern, restricted to returning at most n
items.
If n
substrings are returned, the last substring (the n
th substring) will contain the remainder of the string.
The pattern can be a &str
, char
, or a closure that determines the split.
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.
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, n: usize, pat: P) -> RSplitN<'a, P> where
P: Pattern<'a>,
<P as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
[src]
An iterator over substrings of this string slice, separated by a pattern, starting from the end of the string, restricted to returning at most n
items.
If n
substrings are returned, the last substring (the n
th substring) will contain the remainder of the string.
The pattern can be a &str
, char
, or a closure that determines the split.
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.
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>,
An iterator over the disjoint 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.
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.
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
An iterator over the disjoint 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.
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.
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>,
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.
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.
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
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.
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.
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
[src]
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
.
Basic usage:
let s = " Hello\tworld\t"; assert_eq!("Hello\tworld", s.trim());
fn trim_left(&self) -> &str
[src]
Returns a string slice with leading whitespace removed.
'Whitespace' is defined according to the terms of the Unicode Derived Core Property White_Space
.
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.
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
[src]
Returns a string slice with trailing whitespace removed.
'Whitespace' is defined according to the terms of the Unicode Derived Core Property White_Space
.
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.
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 as Pattern<'a>>::Searcher: DoubleEndedSearcher<'a>,
[src]
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.
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>,
[src]
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.
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.
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 as Pattern<'a>>::Searcher: ReverseSearcher<'a>,
[src]
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.
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.
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 as FromStr>::Err> where
F: FromStr,
[src]
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.
Will return Err
if it's not possible to parse this string slice into the desired type.
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 into_boxed_bytes(self: Box<str>) -> Box<[u8]>
Converts a Box<str>
into a Box<[u8]>
without copying or allocating.
Basic usage:
let s = "this is a string"; let boxed_str = s.to_owned().into_boxed_str(); let boxed_bytes = boxed_str.into_boxed_bytes(); assert_eq!(*boxed_bytes, *s.as_bytes());
fn replace<'a, P>(&'a self, from: P, to: &str) -> String where
P: Pattern<'a>,
[src]
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.
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 replacen<'a, P>(&'a self, pat: P, to: &str, count: usize) -> String where
P: Pattern<'a>,
Replaces first N matches of a pattern with another string.
replacen
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 at most count
times.
Basic usage:
let s = "foo foo 123 foo"; assert_eq!("new new 123 foo", s.replacen("foo", "new", 2)); assert_eq!("faa fao 123 foo", s.replacen('o', "a", 3)); assert_eq!("foo foo new23 foo", s.replacen(char::is_numeric, "new", 1));
When the pattern doesn't match:
let s = "this is old"; assert_eq!(s, s.replacen("cookie monster", "little lamb", 10));
fn to_lowercase(&self) -> String
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
.
Since some characters can expand into multiple characters when changing the case, this function returns a String
instead of modifying the parameter in-place.
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
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
.
Since some characters can expand into multiple characters when changing the case, this function returns a String
instead of modifying the parameter in-place.
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
[src]
Escapes each char in s
with char::escape_debug
.
fn escape_default(&self) -> String
[src]
Escapes each char in s
with char::escape_default
.
fn escape_unicode(&self) -> String
[src]
Escapes each char in s
with char::escape_unicode
.
fn into_string(self: Box<str>) -> String
Converts a Box<str>
into a String
without copying or allocating.
Basic usage:
let string = String::from("birthday gift"); let boxed_str = string.clone().into_boxed_str(); assert_eq!(boxed_str.into_string(), string);
fn repeat(&self, n: usize) -> String
Create a String
by repeating a string n
times.
Basic usage:
assert_eq!("abc".repeat(4), String::from("abcabcabcabc"));
fn is_ascii(&self) -> bool
Checks if all characters in this string are within the ASCII range.
let ascii = "hello!\n"; let non_ascii = "Grüße, Jürgen ❤"; assert!(ascii.is_ascii()); assert!(!non_ascii.is_ascii());
fn to_ascii_uppercase(&self) -> String
Returns a copy of this string where each character is mapped to its ASCII upper case equivalent.
ASCII letters 'a' to 'z' are mapped to 'A' to 'Z', but non-ASCII letters are unchanged.
To uppercase the value in-place, use make_ascii_uppercase
.
To uppercase ASCII characters in addition to non-ASCII characters, use to_uppercase
.
let s = "Grüße, Jürgen ❤"; assert_eq!("GRüßE, JüRGEN ❤", s.to_ascii_uppercase());
fn to_ascii_lowercase(&self) -> String
Returns a copy of this string where each character is mapped to its ASCII lower case equivalent.
ASCII letters 'A' to 'Z' are mapped to 'a' to 'z', but non-ASCII letters are unchanged.
To lowercase the value in-place, use make_ascii_lowercase
.
To lowercase ASCII characters in addition to non-ASCII characters, use to_lowercase
.
let s = "Grüße, Jürgen ❤"; assert_eq!("grüße, jürgen ❤", s.to_ascii_lowercase());
fn eq_ignore_ascii_case(&self, other: &str) -> bool
Checks that two strings are an ASCII case-insensitive match.
Same as to_ascii_lowercase(a) == to_ascii_lowercase(b)
, but without allocating and copying temporaries.
assert!("Ferris".eq_ignore_ascii_case("FERRIS")); assert!("Ferrös".eq_ignore_ascii_case("FERRöS")); assert!(!"Ferrös".eq_ignore_ascii_case("FERRÖS"));
fn make_ascii_uppercase(&mut self)
Converts this string to its ASCII upper case equivalent in-place.
ASCII letters 'a' to 'z' are mapped to 'A' to 'Z', but non-ASCII letters are unchanged.
To return a new uppercased value without modifying the existing one, use to_ascii_uppercase
.
fn make_ascii_lowercase(&mut self)
Converts this string to its ASCII lower case equivalent in-place.
ASCII letters 'A' to 'Z' are mapped to 'a' to 'z', but non-ASCII letters are unchanged.
To return a new lowercased value without modifying the existing one, use to_ascii_lowercase
.
fn is_ascii_alphabetic(&self) -> bool
[src]
Checks if all characters of this string are ASCII alphabetic characters:
fn is_ascii_uppercase(&self) -> bool
[src]
Checks if all characters of this string are ASCII uppercase characters: U+0041 'A' ... U+005A 'Z'.
#![feature(ascii_ctype)] // Only ascii uppercase characters assert!("HELLO".is_ascii_uppercase()); // While all characters are ascii, 'y' and 'e' are not uppercase assert!(!"Bye".is_ascii_uppercase()); // While all characters are uppercase, 'Ü' is not ascii assert!(!"TSCHÜSS".is_ascii_uppercase());
fn is_ascii_lowercase(&self) -> bool
[src]
Checks if all characters of this string are ASCII lowercase characters: U+0061 'a' ... U+007A 'z'.
#![feature(ascii_ctype)] // Only ascii uppercase characters assert!("hello".is_ascii_lowercase()); // While all characters are ascii, 'B' is not lowercase assert!(!"Bye".is_ascii_lowercase()); // While all characters are lowercase, 'Ü' is not ascii assert!(!"tschüss".is_ascii_lowercase());
fn is_ascii_alphanumeric(&self) -> bool
[src]
Checks if all characters of this string are ASCII alphanumeric characters:
fn is_ascii_digit(&self) -> bool
[src]
Checks if all characters of this string are ASCII decimal digit: U+0030 '0' ... U+0039 '9'.
fn is_ascii_hexdigit(&self) -> bool
[src]
Checks if all characters of this string are ASCII hexadecimal digits:
fn is_ascii_punctuation(&self) -> bool
[src]
Checks if all characters of this string are ASCII punctuation characters:
! " # $ % & ' ( ) * + , - . /
, or: ; < = > ? @
, or[ \ ] ^ _ `
, or{ | } ~
fn is_ascii_graphic(&self) -> bool
[src]
Checks if all characters of this string are ASCII graphic characters: U+0021 '@' ... U+007E '~'.
fn is_ascii_whitespace(&self) -> bool
[src]
Checks if all characters of this string are ASCII whitespace characters: U+0020 SPACE, U+0009 HORIZONTAL TAB, U+000A LINE FEED, U+000C FORM FEED, or U+000D CARRIAGE RETURN.
Rust uses the WhatWG Infra Standard's definition of ASCII whitespace. There are several other definitions in wide use. For instance, the POSIX locale includes U+000B VERTICAL TAB as well as all the above characters, but—from the very same specification—the default rule for "field splitting" in the Bourne shell considers only SPACE, HORIZONTAL TAB, and LINE FEED as whitespace.
If you are writing a program that will process an existing file format, check what that format's definition of whitespace is before using this function.
fn is_ascii_control(&self) -> bool
[src]
Checks if all characters of this string are ASCII control characters:
Note that most ASCII whitespace characters are control characters, but SPACE is not.
impl<'a, 'b> PartialEq<String> for str
[src]
fn eq(&self, other: &String) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &String) -> bool
[src]
This method tests for !=
.
impl<'a, 'b> PartialEq<String> for &'a str
[src]
fn eq(&self, other: &String) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &String) -> bool
[src]
This method tests for !=
.
impl<'a, 'b> PartialEq<Cow<'a, str>> for str
[src]
fn eq(&self, other: &Cow<'a, str>) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Cow<'a, str>) -> bool
[src]
This method tests for !=
.
impl<'a, 'b> PartialEq<Cow<'a, str>> for &'b str
[src]
fn eq(&self, other: &Cow<'a, str>) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Cow<'a, str>) -> bool
[src]
This method tests for !=
.
impl ToOwned for str
[src]
type Owned = String
fn to_owned(&self) -> String
[src]
Creates owned data from borrowed data, usually by cloning. Read more
fn clone_into(&self, target: &mut String)
[src]
Uses borrowed data to replace owned data, usually by cloning. Read more
impl ToString for str
fn to_string(&self) -> String
[src]
Converts the given value to a String
. Read more
impl<'a> Default for &'a str
[src]
fn default() -> &'a str
[src]
Creates an empty str
impl PartialOrd<str> for str
[src]
Implements comparison operations on strings.
Strings are compared lexicographically by their byte values. This compares Unicode code points based on their positions in the code charts. This is not necessarily the same as "alphabetical" order, which varies by language and locale. Comparing strings according to culturally-accepted standards requires locale-specific data that is outside the scope of the str
type.
fn partial_cmp(&self, other: &str) -> Option<Ordering>
[src]
This method returns an ordering between self
and other
values if one exists. Read more
fn lt(&self, other: &Rhs) -> bool
[src]
This method tests less than (for self
and other
) and is used by the <
operator. Read more
fn le(&self, other: &Rhs) -> bool
[src]
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
fn gt(&self, other: &Rhs) -> bool
[src]
This method tests greater than (for self
and other
) and is used by the >
operator. Read more
fn ge(&self, other: &Rhs) -> bool
[src]
This method tests greater than or equal to (for self
and other
) and is used by the >=
operator. Read more
impl Eq for str
[src]
impl AsRef<[u8]> for str
[src]
fn as_ref(&self) -> &[u8]
[src]
Performs the conversion.
impl AsRef<str> for str
[src]
fn as_ref(&self) -> &str
[src]
Performs the conversion.
impl Hash for str
[src]
fn hash<H>(&self, state: &mut H) where
H: Hasher,
[src]
Feeds this value into the given [Hasher
]. Read more
fn hash_slice<H>(data: &[Self], state: &mut H) where
H: Hasher,
Feeds a slice of this type into the given [Hasher
]. Read more
impl IndexMut<RangeFull> for str
Implements mutable substring slicing with syntax &mut self[..]
.
Returns a mutable slice of the whole string. This operation can never panic.
Equivalent to &mut self[0 .. len]
.
fn index_mut(&mut self, _index: RangeFull) -> &mut str
[src]
Performs the mutable indexing (container[index]
) operation.
impl IndexMut<RangeInclusive<usize>> for str
[src]
fn index_mut(&mut self, index: RangeInclusive<usize>) -> &mut str
[src]
Performs the mutable indexing (container[index]
) operation.
impl IndexMut<RangeToInclusive<usize>> for str
[src]
fn index_mut(&mut self, index: RangeToInclusive<usize>) -> &mut str
[src]
Performs the mutable indexing (container[index]
) operation.
impl IndexMut<RangeFrom<usize>> for str
Implements mutable substring slicing with syntax &mut self[begin ..]
.
Returns a mutable slice of the string from byte offset begin
to the end of the string.
Equivalent to &mut self[begin .. len]
.
fn index_mut(&mut self, index: RangeFrom<usize>) -> &mut str
[src]
Performs the mutable indexing (container[index]
) operation.
impl IndexMut<Range<usize>> for str
Implements mutable substring slicing with syntax &mut self[begin .. end]
.
Returns a mutable slice of the given string from the byte range [begin
..end
).
This operation is O(1)
.
Panics if begin
or end
does not point to the starting byte offset of a character (as defined by is_char_boundary
). Requires that begin <= end
and end <= len
where len
is the length of the string.
fn index_mut(&mut self, index: Range<usize>) -> &mut str
[src]
Performs the mutable indexing (container[index]
) operation.
impl IndexMut<RangeTo<usize>> for str
Implements mutable substring slicing with syntax &mut self[.. end]
.
Returns a mutable slice of the string from the beginning to byte offset end
.
Equivalent to &mut self[0 .. end]
.
fn index_mut(&mut self, index: RangeTo<usize>) -> &mut str
[src]
Performs the mutable indexing (container[index]
) operation.
impl Display for str
[src]
fn fmt(&self, f: &mut Formatter) -> Result<(), Error>
[src]
Formats the value using the given formatter. Read more
impl Ord for str
[src]
Implements ordering of strings.
Strings are ordered lexicographically by their byte values. This orders Unicode code points based on their positions in the code charts. This is not necessarily the same as "alphabetical" order, which varies by language and locale. Sorting strings according to culturally-accepted standards requires locale-specific data that is outside the scope of the str
type.
fn cmp(&self, other: &str) -> Ordering
[src]
This method returns an Ordering
between self
and other
. Read more
fn max(self, other: Self) -> Self
Compares and returns the maximum of two values. Read more
fn min(self, other: Self) -> Self
Compares and returns the minimum of two values. Read more
impl PartialEq<str> for str
[src]
fn eq(&self, other: &str) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &str) -> bool
[src]
This method tests for !=
.
impl<'a, 'b> Pattern<'a> for &'b str
[src]
Non-allocating substring search.
Will handle the pattern ""
as returning empty matches at each character boundary.
type Searcher = StrSearcher<'a, 'b>
Associated searcher for this pattern
fn into_searcher(self, haystack: &'a str) -> StrSearcher<'a, 'b>
[src]
Constructs the associated searcher from self
and the haystack
to search in. Read more
fn is_prefix_of(self, haystack: &'a str) -> bool
[src]
Checks whether the pattern matches at the front of the haystack
fn is_suffix_of(self, haystack: &'a str) -> bool
[src]
Checks whether the pattern matches at the back of the haystack
fn is_contained_in(self, haystack: &'a str) -> bool
[src]
Checks whether the pattern matches anywhere in the haystack
impl Index<RangeToInclusive<usize>> for str
[src]
type Output = str
The returned type after indexing.
fn index(&self, index: RangeToInclusive<usize>) -> &str
[src]
Performs the indexing (container[index]
) operation.
impl Index<RangeFull> for str
[src]
Implements substring slicing with syntax &self[..]
.
Returns a slice of the whole string. This operation can never panic.
Equivalent to &self[0 .. len]
.
type Output = str
The returned type after indexing.
fn index(&self, _index: RangeFull) -> &str
[src]
Performs the indexing (container[index]
) operation.
impl Index<RangeFrom<usize>> for str
[src]
Implements substring slicing with syntax &self[begin ..]
.
Returns a slice of the string from byte offset begin
to the end of the string.
Equivalent to &self[begin .. len]
.
type Output = str
The returned type after indexing.
fn index(&self, index: RangeFrom<usize>) -> &str
[src]
Performs the indexing (container[index]
) operation.
impl Index<RangeInclusive<usize>> for str
[src]
type Output = str
The returned type after indexing.
fn index(&self, index: RangeInclusive<usize>) -> &str
[src]
Performs the indexing (container[index]
) operation.
impl Index<RangeTo<usize>> for str
[src]
Implements substring slicing with syntax &self[.. end]
.
Returns a slice of the string from the beginning to byte offset end
.
Equivalent to &self[0 .. end]
.
type Output = str
The returned type after indexing.
fn index(&self, index: RangeTo<usize>) -> &str
[src]
Performs the indexing (container[index]
) operation.
impl Index<Range<usize>> for str
[src]
Implements substring slicing with syntax &self[begin .. end]
.
Returns a slice of the given string from the byte range [begin
..end
).
This operation is O(1)
.
Panics if begin
or end
does not point to the starting byte offset of a character (as defined by is_char_boundary
). Requires that begin <= end
and end <= len
where len
is the length of the string.
let s = "Löwe 老虎 Léopard"; assert_eq!(&s[0 .. 1], "L"); assert_eq!(&s[1 .. 9], "öwe 老"); // these will panic: // byte 2 lies within `ö`: // &s[2 ..3]; // byte 8 lies within `老` // &s[1 .. 8]; // byte 100 is outside the string // &s[3 .. 100];
type Output = str
The returned type after indexing.
fn index(&self, index: Range<usize>) -> &str
[src]
Performs the indexing (container[index]
) operation.
impl Debug for str
[src]
fn fmt(&self, f: &mut Formatter) -> Result<(), Error>
[src]
Formats the value using the given formatter. Read more
impl UnicodeStr for str
[src]
fn split_whitespace(&self) -> SplitWhitespace
[src]
fn is_whitespace(&self) -> bool
[src]
fn is_alphanumeric(&self) -> bool
[src]
fn trim(&self) -> &str
[src]
fn trim_left(&self) -> &str
[src]
fn trim_right(&self) -> &str
[src]
impl AsciiExt for str
[src]
type Owned = String
Container type for copied ASCII characters.
fn is_ascii(&self) -> bool
[src]
Checks if the value is within the ASCII range. Read more
fn to_ascii_uppercase(&self) -> Self::Owned
[src]
Makes a copy of the value in its ASCII upper case equivalent. Read more
fn to_ascii_lowercase(&self) -> Self::Owned
[src]
Makes a copy of the value in its ASCII lower case equivalent. Read more
fn eq_ignore_ascii_case(&self, o: &Self) -> bool
[src]
Checks that two values are an ASCII case-insensitive match. Read more
fn make_ascii_uppercase(&mut self)
[src]
Converts this type to its ASCII upper case equivalent in-place. Read more
fn make_ascii_lowercase(&mut self)
[src]
Converts this type to its ASCII lower case equivalent in-place. Read more
fn is_ascii_alphabetic(&self) -> bool
[src]
Checks if the value is an ASCII alphabetic character: U+0041 'A' ... U+005A 'Z' or U+0061 'a' ... U+007A 'z'. For strings, true if all characters in the string are ASCII alphabetic. Read more
fn is_ascii_uppercase(&self) -> bool
[src]
Checks if the value is an ASCII uppercase character: U+0041 'A' ... U+005A 'Z'. For strings, true if all characters in the string are ASCII uppercase. Read more
fn is_ascii_lowercase(&self) -> bool
[src]
Checks if the value is an ASCII lowercase character: U+0061 'a' ... U+007A 'z'. For strings, true if all characters in the string are ASCII lowercase. Read more
fn is_ascii_alphanumeric(&self) -> bool
[src]
Checks if the value is an ASCII alphanumeric character: U+0041 'A' ... U+005A 'Z', U+0061 'a' ... U+007A 'z', or U+0030 '0' ... U+0039 '9'. For strings, true if all characters in the string are ASCII alphanumeric. Read more
fn is_ascii_digit(&self) -> bool
[src]
Checks if the value is an ASCII decimal digit: U+0030 '0' ... U+0039 '9'. For strings, true if all characters in the string are ASCII digits. Read more
fn is_ascii_hexdigit(&self) -> bool
[src]
Checks if the value is an ASCII hexadecimal digit: U+0030 '0' ... U+0039 '9', U+0041 'A' ... U+0046 'F', or U+0061 'a' ... U+0066 'f'. For strings, true if all characters in the string are ASCII hex digits. Read more
fn is_ascii_punctuation(&self) -> bool
[src]
Checks if the value is an ASCII punctuation character: Read more
fn is_ascii_graphic(&self) -> bool
[src]
Checks if the value is an ASCII graphic character: U+0021 '@' ... U+007E '~'. For strings, true if all characters in the string are ASCII punctuation. Read more
fn is_ascii_whitespace(&self) -> bool
[src]
Checks if the value is an ASCII whitespace character: U+0020 SPACE, U+0009 HORIZONTAL TAB, U+000A LINE FEED, U+000C FORM FEED, or U+000D CARRIAGE RETURN. For strings, true if all characters in the string are ASCII whitespace. Read more
fn is_ascii_control(&self) -> bool
[src]
Checks if the value is an ASCII control character: U+0000 NUL ... U+001F UNIT SEPARATOR, or U+007F DELETE. Note that most ASCII whitespace characters are control characters, but SPACE is not. Read more
impl PartialEq<OsString> for str
[src]
fn eq(&self, other: &OsString) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Rhs) -> bool
[src]
This method tests for !=
.
impl PartialEq<OsStr> for str
[src]
fn eq(&self, other: &OsStr) -> bool
[src]
This method tests for self
and other
values to be equal, and is used by ==
. Read more
fn ne(&self, other: &Rhs) -> bool
[src]
This method tests for !=
.
impl AsRef<OsStr> for str
[src]
fn as_ref(&self) -> &OsStr
[src]
Performs the conversion.
impl ToSocketAddrs for str
[src]
type Iter = IntoIter<SocketAddr>
Returned iterator over socket addresses which this type may correspond to. Read more
fn to_socket_addrs(&self) -> Result<IntoIter<SocketAddr>>
[src]
Converts this object to an iterator of resolved SocketAddr
s. Read more
impl AsRef<Path> for str
[src]
fn as_ref(&self) -> &Path
[src]
Performs the conversion.
© 2010 The Rust Project Developers
Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/std/primitive.str.html