arrayvec 0.3.20

A vector with a fixed capacity, it can be stored on the stack too. Implements fixed capacity ArrayVec and ArrayString.

Struct arrayvec::ArrayString [] [src]

pub struct ArrayString<A: Array<Item=u8>> { /* fields omitted */ }

A string with a fixed capacity.

The ArrayString is a string backed by a fixed size array. It keeps track of its length.

The string is a contiguous value that you can store directly on the stack if needed.

Methods

impl<A: Array<Item=u8>> ArrayString<A>
[src]

Create a new empty ArrayString.

Capacity is inferred from the type parameter.

use arrayvec::ArrayString;

let mut string = ArrayString::<[_; 16]>::new();
string.push_str("foo");
assert_eq!(&string[..], "foo");
assert_eq!(string.capacity(), 16);Run

Create a new ArrayString from a str.

Capacity is inferred from the type parameter.

Errors if the backing array is not large enough to fit the string.

use arrayvec::ArrayString;

let mut string = ArrayString::<[_; 3]>::from("foo").unwrap();
assert_eq!(&string[..], "foo");
assert_eq!(string.len(), 3);
assert_eq!(string.capacity(), 3);Run

Return the capacity of the ArrayString.

use arrayvec::ArrayString;

let string = ArrayString::<[_; 3]>::new();
assert_eq!(string.capacity(), 3);Run

Return if the ArrayString is completely filled.

use arrayvec::ArrayString;

let mut string = ArrayString::<[_; 1]>::new();
assert!(!string.is_full());
string.push_str("A");
assert!(string.is_full());Run

Adds the given char to the end of the string.

Returns Ok if the push succeeds.

Errors if the backing array is not large enough to fit the additional char.

use arrayvec::ArrayString;

let mut string = ArrayString::<[_; 2]>::new();

string.push('a').unwrap();
string.push('b').unwrap();
let overflow = string.push('c');

assert_eq!(&string[..], "ab");
assert_eq!(overflow.unwrap_err().element(), 'c');Run

Adds the given string slice to the end of the string.

Returns Ok if the push succeeds.

Errors if the backing array is not large enough to fit the string.

use arrayvec::ArrayString;

let mut string = ArrayString::<[_; 2]>::new();

string.push_str("a").unwrap();
let overflow1 = string.push_str("bc");
string.push_str("d").unwrap();
let overflow2 = string.push_str("ef");

assert_eq!(&string[..], "ad");
assert_eq!(overflow1.unwrap_err().element(), "bc");
assert_eq!(overflow2.unwrap_err().element(), "ef");Run

Make the string empty.

Set the strings's length.

May panic if length is greater than the capacity.

This function is unsafe because it changes the notion of the number of “valid” bytes in the string. Use with care.

Return a string slice of the whole ArrayString.

Methods from Deref<Target=str>

Returns the length of self.

This length is in bytes, not chars 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);Run

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());Run

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));Run

Converts a string slice to a byte slice.

Examples

Basic usage:

let bytes = "bors".as_bytes();
assert_eq!(b"bors", bytes);Run

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();Run

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 before end.
  • begin and end must be byte positions within the string slice.
  • begin and end 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));
}Run

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 before end.
  • begin and end must be byte positions within the string slice.
  • begin and end must lie on UTF-8 sequence boundaries.

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);Run

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);Run

Returns an iterator over the chars 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());Run

Remember, chars 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());Run

Returns an iterator over the chars 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 chars, 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());Run

Remember, chars 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());Run

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());Run

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());Run

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());Run

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());Run

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());Run

Deprecated since 1.4.0

: use lines() instead now

An iterator over the lines of a string.

Returns an iterator of u16 over the string encoded as UTF-16.

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"));Run

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"));Run

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"));Run

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));Run

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));Run

Not finding the pattern:

let s = "Löwe 老虎 Léopard";
let x: &[_] = &['1', '2'];

assert_eq!(s.find(x), None);Run

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));Run

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));Run

Not finding the pattern:

let s = "Löwe 老虎 Léopard";
let x: &[_] = &['1', '2'];

assert_eq!(s.rfind(x), None);Run

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"]);Run

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"]);Run

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"]);Run

Contiguous separators are separated by the empty string.

let x = "(///)".to_string();
let d: Vec<_> = x.split('/').collect();;

assert_eq!(d, &["(", "", "", ")"]);Run

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", ""]);Run

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", ""]);Run

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"]);Run

It does not give you:

assert_eq!(d, &["a", "b", "c"]);Run

Use split_whitespace() for this behavior.

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"]);Run

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"]);Run

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", ""]);Run

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"]);Run

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, [""]);Run

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"]);Run

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"]);Run

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"]);Run

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"]);Run

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"]);Run

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`Run

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`Run

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());Run

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());Run

Directionality:

let s = "  English";
assert!(Some('E') == s.trim_left().chars().next());

let s = "  עברית";
assert!(Some('ע') == s.trim_left().chars().next());Run

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());Run

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());Run

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");Run

A more complex pattern, using a closure:

assert_eq!("1foo1barXX".trim_matches(|c| c == '1' || c == 'X'), "foo1bar");Run

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");Run

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");Run

A more complex pattern, using a closure:

assert_eq!("1fooX".trim_left_matches(|c| c == '1' || c == 'X'), "fooX");Run

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);Run

Using the 'turbofish' instead of annotating four:

let four = "4".parse::<u32>();

assert_eq!(Ok(4), four);Run

Failing to parse:

let nope = "j".parse::<u32>();

assert!(nope.is_err());Run

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"));Run

When the pattern doesn't match:

let s = "this is old";
assert_eq!(s, s.replace("cookie monster", "little lamb"));Run

Unstable (str_replacen)

: only need to replace first N matches

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 N times.

Examples

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));Run

When the pattern doesn't match:

let s = "this is old";
assert_eq!(s, s.replacen("cookie monster", "little lamb", 10));Run

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());Run

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());Run

Languages without case are not changed:

let new_year = "农历新年";

assert_eq!(new_year, new_year.to_lowercase());Run

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());Run

Scripts without case are not changed:

let new_year = "农历新年";

assert_eq!(new_year, new_year.to_uppercase());Run

Unstable (str_escape)

: return type may change to be an iterator

Escapes each char in s with char::escape_debug.

Unstable (str_escape)

: return type may change to be an iterator

Escapes each char in s with char::escape_default.

Unstable (str_escape)

: return type may change to be an iterator

Escapes each char in s with char::escape_unicode.

Converts a Box<str> into a String without copying or allocating.

Examples

Basic usage:

let string = String::from("birthday gift");
let boxed_str = string.clone().into_boxed_str();

assert_eq!(boxed_str.into_string(), string);Run

Trait Implementations

impl<A: Copy + Array<Item=u8>> Copy for ArrayString<A> where A::Index: Copy
[src]

impl<A: Array<Item=u8>> Deref for ArrayString<A>
[src]

The resulting type after dereferencing

The method called to dereference a value

impl<A: Array<Item=u8>> DerefMut for ArrayString<A>
[src]

The method called to mutably dereference a value

impl<A: Array<Item=u8>> PartialEq for ArrayString<A>
[src]

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

impl<A: Array<Item=u8>> PartialEq<str> for ArrayString<A>
[src]

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

impl<A: Array<Item=u8>> Eq for ArrayString<A>
[src]

impl<A: Array<Item=u8>> Hash for ArrayString<A>
[src]

Feeds this value into the state given, updating the hasher as necessary.

Feeds a slice of this type into the state provided.

impl<A: Array<Item=u8>> Borrow<str> for ArrayString<A>
[src]

Immutably borrows from an owned value. Read more

impl<A: Array<Item=u8>> AsRef<str> for ArrayString<A>
[src]

Performs the conversion.

impl<A: Array<Item=u8>> Debug for ArrayString<A>
[src]

Formats the value using the given formatter.

impl<A: Array<Item=u8>> Display for ArrayString<A>
[src]

Formats the value using the given formatter.

impl<A: Array<Item=u8>> Write for ArrayString<A>
[src]

Write appends written data to the end of the string.

Writes a char into this writer, returning whether the write succeeded. Read more

Writes a slice of bytes into this writer, returning whether the write succeeded. Read more

Glue for usage of the write! macro with implementors of this trait. Read more

impl<A: Array<Item=u8> + Copy> Clone for ArrayString<A>
[src]

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more