Enum mime::TopLevel

pub enum TopLevel {
    Star,
    Text,
    Image,
    Audio,
    Video,
    Application,
    Multipart,
    Message,
    Model,
    Ext(String),
}

Variants

Star
Text
Image
Audio
Video
Application
Multipart
Message
Model
Ext

Methods

impl TopLevel

fn as_str(&self) -> &str

Methods from Deref<Target=str>

fn len(&self) -> usize

Returns the length of self in bytes.

Examples

assert_eq!("foo".len(), 3);
assert_eq!("ƒoo".len(), 4); // fancy f!

fn is_empty(&self) -> bool

Returns true if this slice has a length of zero bytes.

Examples

assert!("".is_empty());

fn width(&self, is_cjk: bool) -> usize

Deprecated since 1.0.0

: use the crates.io unicode-width library instead

Returns a string's displayed width in columns.

Control characters have zero width.

is_cjk determines behavior for characters in the Ambiguous category: if is_cjk is true, these are 2 columns wide; otherwise, they are 1. In CJK locales, is_cjk should be true, else it should be false. Unicode Standard Annex #11 recommends that these characters be treated as 1 column (i.e., is_cjk = false) if the locale is unknown.

fn is_char_boundary(&self, index: usize) -> bool

Unstable

: it is unclear whether this method pulls its weight with the existence of the char_indices iterator or this method may want to be replaced with checked slicing

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.

Panics

Panics 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]

Converts self to a byte slice.

Examples

assert_eq!("bors".as_bytes(), b"bors");

fn as_ptr(&self) -> *const u8

Returns a raw pointer to the &str's buffer.

The caller must ensure that the string outlives this pointer, and that it is not reallocated (e.g. by pushing to the string).

Examples

let s = "Hello";
let p = s.as_ptr();

unsafe fn slice_unchecked(&self, begin: usize, end: usize) -> &str

Takes a bytewise slice from a string.

Returns the substring from [begin..end).

Unsafety

Caller must check both UTF-8 character boundaries and the boundaries of the entire slice as well.

Examples

let s = "Löwe 老虎 Léopard";

unsafe {
    assert_eq!(s.slice_unchecked(0, 21), "Löwe 老虎 Léopard");
}

fn slice_chars(&self, begin: usize, end: usize) -> &str

Unstable

: may have yet to prove its worth

Returns a slice of the string from the character range [begin..end).

That is, start at the begin-th code point of the string and continue to the end-th code point. This does not detect or handle edge cases such as leaving a combining character as the first code point of the string.

Due to the design of UTF-8, this operation is O(end). Use slicing syntax if you want to use byte indices rather than codepoint indices.

Panics

Panics if begin > end or the either begin or end are beyond the last character of the string.

Examples

let s = "Löwe 老虎 Léopard";

assert_eq!(s.slice_chars(0, 4), "Löwe");
assert_eq!(s.slice_chars(5, 7), "老虎");

fn char_range_at(&self, start: usize) -> CharRange

Unstable

: often replaced by char_indices, this method may be removed in favor of just char_at() or eventually removed altogether

Given a byte position, return the next char and its index.

This can be used to iterate over the Unicode characters of a string.

Panics

If i is greater than or equal to the length of the string. If i is not the index of the beginning of a valid UTF-8 character.

Examples

This example manually iterates through the characters of a string; this should normally be done by .chars() or .char_indices().

use std::str::CharRange;

let s = "中华Việt Nam";
let mut i = 0;
while i < s.len() {
    let CharRange {ch, next} = s.char_range_at(i);
    println!("{}: {}", i, ch);
    i = next;
}

This outputs:

0: 中
3: 华
6: V
7: i
8: ệ
11: t
12:
13: N
14: a
15: m

fn char_range_at_reverse(&self, start: usize) -> CharRange

Unstable

: often replaced by char_indices, this method may be removed in favor of just char_at_reverse() or eventually removed altogether

Given a byte position, return the previous char and its position.

This function can be used to iterate over a Unicode string in reverse.

Returns 0 for next index if called on start index 0.

Panics

If i is greater than the length of the string. If i is not an index following a valid UTF-8 character.

Examples

This example manually iterates through the characters of a string; this should normally be done by .chars().rev() or .char_indices().

use std::str::CharRange;

let s = "中华Việt Nam";
let mut i = s.len();
while i > 0 {
    let CharRange {ch, next} = s.char_range_at_reverse(i);
    println!("{}: {}", i, ch);
    i = next;
}

This outputs:

16: m
15: a
14: N
13:
12: t
11: ệ
8: i
7: V
6: 华
3: 中

fn char_at(&self, i: usize) -> char

Unstable

: frequently replaced by the chars() iterator, this method may be removed or possibly renamed in the future; it is normally replaced by chars/char_indices iterators or by getting the first char from a subslice

Given a byte position, return the char at that position.

Panics

If i is greater than or equal to the length of the string. If i is not the index of the beginning of a valid UTF-8 character.

Examples

let s = "abπc";
assert_eq!(s.char_at(1), 'b');
assert_eq!(s.char_at(2), 'π');

fn char_at_reverse(&self, i: usize) -> char

Unstable

: see char_at for more details, but reverse semantics are also somewhat unclear, especially with which cases generate panics

Given a byte position, return the char at that position, counting from the end.

Panics

If i is greater than the length of the string. If i is not an index following a valid UTF-8 character.

Examples

let s = "abπc";
assert_eq!(s.char_at_reverse(1), 'a');
assert_eq!(s.char_at_reverse(2), 'b');

fn slice_shift_char(&self) -> Option<(char, &str)>

Unstable

: awaiting conventions about shifting and slices and may not be warranted with the existence of the chars and/or char_indices iterators

Retrieves the first character from a &str and returns it.

This does not allocate a new string; instead, it returns a slice that points one character beyond the character that was shifted.

If the slice does not contain any characters, None is returned instead.

Examples

let s = "Löwe 老虎 Léopard";
let (c, s1) = s.slice_shift_char().unwrap();

assert_eq!(c, 'L');
assert_eq!(s1, "öwe 老虎 Léopard");

let (c, s2) = s1.slice_shift_char().unwrap();

assert_eq!(c, 'ö');
assert_eq!(s2, "we 老虎 Léopard");

fn split_at(&self, mid: usize) -> (&str, &str)

Unstable

: library is unlikely to be stabilized with the current layout and name, use std::collections instead

Divide one string slice into two at an index.

The index mid is a byte offset from the start of the string that must be on a character boundary.

Return slices &self[..mid] and &self[mid..].

Panics

Panics if mid is beyond the last character of the string, or if it is not on a character boundary.

Examples

let s = "Löwe 老虎 Léopard";
let first_space = s.find(' ').unwrap_or(s.len());
let (a, b) = s.split_at(first_space);

assert_eq!(a, "Löwe");
assert_eq!(b, " 老虎 Léopard");

fn chars(&self) -> Chars

An iterator over the codepoints of self.

Examples

let v: Vec<char> = "abc åäö".chars().collect();

assert_eq!(v, ['a', 'b', 'c', ' ', 'å', 'ä', 'ö']);

fn char_indices(&self) -> CharIndices

An iterator over the characters of self and their byte offsets.

Examples

let v: Vec<(usize, char)> = "abc".char_indices().collect();
let b = vec![(0, 'a'), (1, 'b'), (2, 'c')];

assert_eq!(v, b);

fn bytes(&self) -> Bytes

An iterator over the bytes of self.

Examples

let v: Vec<u8> = "bors".bytes().collect();

assert_eq!(v, b"bors".to_vec());

fn split_whitespace(&self) -> SplitWhitespace

An iterator over the non-empty substrings of self which contain no whitespace, and which are separated by any amount of whitespace.

Examples

let some_words = " Mary   had\ta little  \n\t lamb";
let v: Vec<&str> = some_words.split_whitespace().collect();

assert_eq!(v, ["Mary", "had", "a", "little", "lamb"]);

fn words(&self) -> SplitWhitespace

Deprecated since 1.1.0

: words() will be removed. Use split_whitespace() instead

An iterator over the non-empty substrings of self which contain no whitespace, and which are separated by any amount of whitespace.

Examples

let some_words = " Mary   had\ta little  \n\t lamb";
let v: Vec<&str> = some_words.words().collect();

assert_eq!(v, ["Mary", "had", "a", "little", "lamb"]);

fn lines(&self) -> Lines

An iterator over the lines of a string, separated by \n.

This does not include the empty string after a trailing \n.

Examples

let four_lines = "foo\nbar\n\nbaz";
let v: Vec<&str> = four_lines.lines().collect();

assert_eq!(v, ["foo", "bar", "", "baz"]);

Leaving off the trailing character:

let four_lines = "foo\nbar\n\nbaz\n";
let v: Vec<&str> = four_lines.lines().collect();

assert_eq!(v, ["foo", "bar", "", "baz"]);

fn lines_any(&self) -> LinesAny

An iterator over the lines of a string, separated by either \n or \r\n.

As with .lines(), this does not include an empty trailing line.

Examples

let four_lines = "foo\r\nbar\n\r\nbaz";
let v: Vec<&str> = four_lines.lines_any().collect();

assert_eq!(v, ["foo", "bar", "", "baz"]);

Leaving off the trailing character:

let four_lines = "foo\r\nbar\n\r\nbaz\n";
let v: Vec<&str> = four_lines.lines_any().collect();

assert_eq!(v, ["foo", "bar", "", "baz"]);

fn nfd_chars(&self) -> Decompositions

Deprecated since 1.0.0

: use the crates.io unicode-normalization library instead

Returns an iterator over the string in Unicode Normalization Form D (canonical decomposition).

fn nfkd_chars(&self) -> Decompositions

Deprecated since 1.0.0

: use the crates.io unicode-normalization library instead

Returns an iterator over the string in Unicode Normalization Form KD (compatibility decomposition).

fn nfc_chars(&self) -> Recompositions

Deprecated since 1.0.0

: use the crates.io unicode-normalization library instead

An Iterator over the string in Unicode Normalization Form C (canonical decomposition followed by canonical composition).

fn nfkc_chars(&self) -> Recompositions

Deprecated since 1.0.0

: use the crates.io unicode-normalization library instead

An Iterator over the string in Unicode Normalization Form KC (compatibility decomposition followed by canonical composition).

fn graphemes(&self, is_extended: bool) -> Graphemes

Deprecated since 1.0.0

: use the crates.io unicode-segmentation library instead

Returns an iterator over the grapheme clusters of self.

If is_extended is true, the iterator is over the extended grapheme clusters; otherwise, the iterator is over the legacy grapheme clusters. UAX#29 recommends extended grapheme cluster boundaries for general processing.

Examples

let gr1 = "a\u{310}e\u{301}o\u{308}\u{332}".graphemes(true).collect::<Vec<&str>>();
let b: &[_] = &["a\u{310}", "e\u{301}", "o\u{308}\u{332}"];

assert_eq!(&gr1[..], b);

let gr2 = "a\r\nb🇷🇺🇸🇹".graphemes(true).collect::<Vec<&str>>();
let b: &[_] = &["a", "\r\n", "b", "🇷🇺🇸🇹"];

assert_eq!(&gr2[..], b);

fn grapheme_indices(&self, is_extended: bool) -> GraphemeIndices

Deprecated since 1.0.0

: use the crates.io unicode-segmentation library instead

Returns an iterator over the grapheme clusters of self and their byte offsets. See graphemes() for more information.

Examples

let gr_inds = "a̐éö̲\r\n".grapheme_indices(true).collect::<Vec<(usize, &str)>>();
let b: &[_] = &[(0, "a̐"), (3, "é"), (6, "ö̲"), (11, "\r\n")];

assert_eq!(&gr_inds[..], b);

fn utf16_units(&self) -> Utf16Units

Unstable

: this functionality may only be provided by libunicode

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>

Returns true if self contains another &str.

Examples

assert!("bananas".contains("nana"));

assert!(!"bananas".contains("foobar"));

fn starts_with<'a, P>(&'a self, pat: P) -> bool where P: Pattern<'a>

Returns true if the given &str is a prefix of the string.

Examples

assert!("banana".starts_with("ba"));

fn ends_with<'a, P>(&'a self, pat: P) -> bool where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>

Returns true if the given &str is a suffix of the string.

Examples

assert!("banana".ends_with("nana"));

fn find<'a, P>(&'a self, pat: P) -> Option<usize> where P: Pattern<'a>

Returns the byte index of the first character of self that matches the pattern, if it exists.

Returns None if it doesn't exist.

The pattern can be a simple &str, char, or a closure that determines the split.

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>

Returns the byte index of the last character of self that matches the pattern, if it exists.

Returns None if it doesn't exist.

The pattern can be a simple &str, char, or a closure that determines the split.

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>

An iterator over substrings of self, separated by characters matched by a pattern.

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.

Iterator behavior

The returned iterator will be double ended 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, rsplit() 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"]);

This 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"]);

fn rsplit<'a, P>(&'a self, pat: P) -> RSplit<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>

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.

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, split() 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>

An iterator over substrings of self, separated by characters matched by a pattern.

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 will be double ended 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, rsplit_terminator() can be used.

Examples

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>

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, split_terminator() 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>

An iterator over substrings of self, separated by a pattern, restricted to returning at most count items.

The last element returned, if any, will contain the remainder of the string. 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.

Iterator behavior

The returned iterator will not be double ended, because it is not efficient to support.

If the pattern allows a reverse search, rsplitn() 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>

An iterator over substrings of self, 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.

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.

Iterator behavior

The returned iterator will not be double ended, because it is not efficient to support.

splitn() can be used for splitting from the front.

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>

An iterator over the matches of a pattern within self.

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.

Iterator behavior

The returned iterator will be double ended 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, rmatches() can be used.

Examples

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>

An iterator over the matches of a pattern within self, 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.

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, matches() can be used.

Examples

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>

Unstable

: might have its iterator type changed

An iterator over the start and end indices of the disjoint matches of a pattern within self.

For matches of pat within self that overlap, only the indices corresponding to the first match are returned.

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.

Iterator behavior

The returned iterator will be double ended 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, rmatch_indices() can be used.

Examples

let v: Vec<(usize, usize)> = "abcXXXabcYYYabc".match_indices("abc").collect();
assert_eq!(v, [(0, 3), (6, 9), (12, 15)]);

let v: Vec<(usize, usize)> = "1abcabc2".match_indices("abc").collect();
assert_eq!(v, [(1, 4), (4, 7)]);

let v: Vec<(usize, usize)> = "ababa".match_indices("aba").collect();
assert_eq!(v, [(0, 3)]); // only the first `aba`

fn rmatch_indices<'a, P>(&'a self, pat: P) -> RMatchIndices<'a, P> where P: Pattern<'a>, P::Searcher: ReverseSearcher<'a>

Unstable

: might have its iterator type changed

An iterator over the start and end indices of the disjoint matches of a pattern within self, yielded in reverse order.

For matches of pat within self that overlap, only the indices corresponding to the last match are returned.

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.

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, match_indices() can be used.

Examples

let v: Vec<(usize, usize)> = "abcXXXabcYYYabc".rmatch_indices("abc").collect();
assert_eq!(v, [(12, 15), (6, 9), (0, 3)]);

let v: Vec<(usize, usize)> = "1abcabc2".rmatch_indices("abc").collect();
assert_eq!(v, [(4, 7), (1, 4)]);

let v: Vec<(usize, usize)> = "ababa".rmatch_indices("aba").collect();
assert_eq!(v, [(2, 5)]); // only the last `aba`

fn subslice_offset(&self, inner: &str) -> usize

Unstable

: awaiting convention about comparability of arbitrary slices

Returns the byte offset of an inner slice relative to an enclosing outer slice.

Panics

Panics if inner is not a direct slice contained within self.

Examples

let string = "a\nb\nc";
let lines: Vec<&str> = string.lines().collect();

assert!(string.subslice_offset(lines[0]) == 0); // &"a"
assert!(string.subslice_offset(lines[1]) == 2); // &"b"
assert!(string.subslice_offset(lines[2]) == 4); // &"c"

fn trim(&self) -> &str

Returns a &str with leading and trailing whitespace removed.

Examples

let s = " Hello\tworld\t";
assert_eq!(s.trim(), "Hello\tworld");

fn trim_left(&self) -> &str

Returns a &str with leading whitespace removed.

Examples

let s = " Hello\tworld\t";
assert_eq!(s.trim_left(), "Hello\tworld\t");

fn trim_right(&self) -> &str

Returns a &str with trailing whitespace removed.

Examples

let s = " Hello\tworld\t";
assert_eq!(s.trim_right(), " Hello\tworld");

fn trim_matches<'a, P>(&'a self, pat: P) -> &'a str where P: Pattern<'a>, P::Searcher: DoubleEndedSearcher<'a>

Returns a string with all pre- and suffixes that match a pattern repeatedly removed.

The pattern can be a simple char, or a closure that determines the split.

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>

Returns a string with all prefixes that match a pattern repeatedly removed.

The pattern can be a simple &str, char, or a closure that determines the split.

Examples

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>

Returns a string with all suffixes that match a pattern repeatedly removed.

The pattern can be a simple &str, char, or a closure that determines the split.

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

Parses self into the specified type.

Failure

Will return Err if it's not possible to parse self into the type.

Example

assert_eq!("4".parse::<u32>(), Ok(4));

Failing:

assert!("j".parse::<u32>().is_err());

fn replace(&self, from: &str, to: &str) -> String

Replaces all occurrences of one string with another.

replace takes two arguments, a sub-&str to find in self, and a second &str to replace it with. If the original &str isn't found, no change occurs.

Examples

let s = "this is old";

assert_eq!(s.replace("old", "new"), "this is new");

When a &str isn't found:

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

fn to_lowercase(&self) -> String

Returns the lowercase equivalent of this string.

Examples

#![feature(str_casing)]

let s = "HELLO";
assert_eq!(s.to_lowercase(), "hello");

fn to_uppercase(&self) -> String

Returns the uppercase equivalent of this string.

Examples

#![feature(str_casing)]

let s = "hello";
assert_eq!(s.to_uppercase(), "HELLO");

fn escape_default(&self) -> String

Unstable

: return type may change to be an iterator

Escapes each char in s with char::escape_default.

fn escape_unicode(&self) -> String

Unstable

: return type may change to be an iterator

Escapes each char in s with char::escape_unicode.

Trait Implementations

impl Deref for TopLevel

type Target = str

fn deref(&self) -> &str

impl PartialEq for TopLevel

fn eq(&self, other: &TopLevel) -> bool

fn ne(&self, other: &Rhs) -> bool

impl PartialEq<String> for TopLevel

fn eq(&self, other: &String) -> bool

fn ne(&self, other: &Rhs) -> bool

impl PartialEq<str> for TopLevel

fn eq(&self, other: &str) -> bool

fn ne(&self, other: &Rhs) -> bool

impl<'a> PartialEq<&'a str> for TopLevel

fn eq(&self, other: &&'a str) -> bool

fn ne(&self, other: &Rhs) -> bool

impl Display for TopLevel

fn fmt(&self, fmt: &mut Formatter) -> Result

impl FromStr for TopLevel

type Err = ()

fn from_str(s: &str) -> Result<TopLevel, ()>

Derived Implementations

impl Debug for TopLevel

fn fmt(&self, __arg_0: &mut Formatter) -> Result

impl Clone for TopLevel

fn clone(&self) -> TopLevel

fn clone_from(&mut self, source: &Self)