pub enum HirKind {
Empty,
Literal(Literal),
Class(Class),
Look(Look),
Repetition(Repetition),
Capture(Capture),
Concat(Vec<Hir>),
Alternation(Vec<Hir>),
}
Expand description
The underlying kind of an arbitrary Hir
expression.
An HirKind
is principally useful for doing case analysis on the type
of a regular expression. If you’re looking to build new Hir
values,
then you must use the smart constructors defined on Hir
, like
Hir::repetition
, to build new Hir
values. The API intentionally does
not expose any way of building an Hir
directly from an HirKind
.
Variants§
Empty
The empty regular expression, which matches everything, including the empty string.
Literal(Literal)
A literalstring that matches exactly these bytes.
Class(Class)
A single character class that matches any of the characters in the class. A class can either consist of Unicode scalar values as characters, or it can use bytes.
A class may be empty. In which case, it matches nothing.
Look(Look)
A look-around assertion. A look-around match always has zero length.
Repetition(Repetition)
A repetition operation applied to a sub-expression.
Capture(Capture)
A capturing group, which contains a sub-expression.
Concat(Vec<Hir>)
A concatenation of expressions.
A concatenation matches only if each of its sub-expressions match one after the other.
Concatenations are guaranteed by Hir
’s smart constructors to always
have at least two sub-expressions.
Alternation(Vec<Hir>)
An alternation of expressions.
An alternation matches only if at least one of its sub-expressions match. If multiple sub-expressions match, then the leftmost is preferred.
Alternations are guaranteed by Hir
’s smart constructors to always
have at least two sub-expressions.
Implementations§
Trait Implementations§
impl Eq for HirKind
impl StructuralPartialEq for HirKind
Auto Trait Implementations§
impl Freeze for HirKind
impl RefUnwindSafe for HirKind
impl Send for HirKind
impl Sync for HirKind
impl Unpin for HirKind
impl UnwindSafe for HirKind
Blanket Implementations§
Source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere
T: ?Sized,
Source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Source§impl<T> CloneToUninit for Twhere
T: Clone,
impl<T> CloneToUninit for Twhere
T: Clone,
Source§unsafe fn clone_to_uninit(&self, dst: *mut T)
unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)