pub struct Captures<'t> { /* private fields */ }Expand description
Captures represents a group of captured strings for a single match.
The 0th capture always corresponds to the entire match. Each subsequent
index corresponds to the next capture group in the regex. If a capture
group is named, then the matched string is also available via the name
method. (Note that the 0th capture is always unnamed and so must be
accessed with the get method.)
Positions returned from a capture group are always byte indices.
't is the lifetime of the matched text.
Implementations§
source§impl<'t> Captures<'t>
impl<'t> Captures<'t>
sourcepub fn get(&self, i: usize) -> Option<Match<'t>>
pub fn get(&self, i: usize) -> Option<Match<'t>>
Returns the match associated with the capture group at index i. If
i does not correspond to a capture group, or if the capture group
did not participate in the match, then None is returned.
Examples
Get the text of the match with a default of an empty string if this group didn’t participate in the match:
let re = Regex::new(r"[a-z]+(?:([0-9]+)|([A-Z]+))").unwrap();
let caps = re.captures("abc123").unwrap();
let text1 = caps.get(1).map_or("", |m| m.as_str());
let text2 = caps.get(2).map_or("", |m| m.as_str());
assert_eq!(text1, "123");
assert_eq!(text2, "");sourcepub fn name(&self, name: &str) -> Option<Match<'t>>
pub fn name(&self, name: &str) -> Option<Match<'t>>
Returns the match for the capture group named name. If name isn’t a
valid capture group or didn’t match anything, then None is returned.
sourcepub fn iter<'c>(&'c self) -> SubCaptureMatches<'c, 't> ⓘ
pub fn iter<'c>(&'c self) -> SubCaptureMatches<'c, 't> ⓘ
An iterator that yields all capturing matches in the order in which
they appear in the regex. If a particular capture group didn’t
participate in the match, then None is yielded for that capture.
The first match always corresponds to the overall match of the regex.
sourcepub fn expand(&self, replacement: &str, dst: &mut String)
pub fn expand(&self, replacement: &str, dst: &mut String)
Expands all instances of $name in replacement to the corresponding
capture group name, and writes them to the dst buffer given.
name may be an integer corresponding to the index of the capture
group (counted by order of opening parenthesis where 0 is the
entire match) or it can be a name (consisting of letters, digits or
underscores) corresponding to a named capture group.
If name isn’t a valid capture group (whether the name doesn’t exist
or isn’t a valid index), then it is replaced with the empty string.
The longest possible name consisting of the characters [_0-9A-Za-z]
is used. e.g., $1a looks up the capture group named 1a and not the
capture group at index 1. To exert more precise control over the
name, or to refer to a capture group name that uses characters outside
of [_0-9A-Za-z], use braces, e.g., ${1}a or ${foo[bar].baz}. When
using braces, any sequence of characters is permitted. If the sequence
does not refer to a capture group name in the corresponding regex, then
it is replaced with an empty string.
To write a literal $ use $$.
Trait Implementations§
source§impl<'t, 'i> Index<&'i str> for Captures<'t>
impl<'t, 'i> Index<&'i str> for Captures<'t>
Get a group by name.
't is the lifetime of the matched text and 'i is the lifetime
of the group name (the index).
The text can’t outlive the Captures object if this method is
used, because of how Index is defined (normally a[i] is part
of a and can’t outlive it); to do that, use name instead.
Panics
If there is no group named by the given value.
source§impl<'t> Index<usize> for Captures<'t>
impl<'t> Index<usize> for Captures<'t>
Get a group by index.
't is the lifetime of the matched text.
The text can’t outlive the Captures object if this method is
used, because of how Index is defined (normally a[i] is part
of a and can’t outlive it); to do that, use get() instead.
Panics
If there is no group at the given index.