pub struct Cache { /* private fields */ }
Expand description
A cache represents mutable state that a PikeVM
requires during a
search.
For a given PikeVM
, its corresponding cache may be created either via
PikeVM::create_cache
, or via Cache::new
. They are equivalent in
every way, except the former does not require explicitly importing Cache
.
A particular Cache
is coupled with the PikeVM
from which it
was created. It may only be used with that PikeVM
. A cache and its
allocations may be re-purposed via Cache::reset
, in which case, it can
only be used with the new PikeVM
(and not the old one).
Implementations§
source§impl Cache
impl Cache
sourcepub fn new(re: &PikeVM) -> Cache
pub fn new(re: &PikeVM) -> Cache
Create a new PikeVM
cache.
A potentially more convenient routine to create a cache is
PikeVM::create_cache
, as it does not require also importing the
Cache
type.
If you want to reuse the returned Cache
with some other PikeVM
,
then you must call Cache::reset
with the desired PikeVM
.
sourcepub fn reset(&mut self, re: &PikeVM)
pub fn reset(&mut self, re: &PikeVM)
Reset this cache such that it can be used for searching with a
different PikeVM
.
A cache reset permits reusing memory already allocated in this cache
with a different PikeVM
.
§Example
This shows how to re-purpose a cache for use with a different PikeVM
.
use regex_automata::{nfa::thompson::pikevm::PikeVM, Match};
let re1 = PikeVM::new(r"\w")?;
let re2 = PikeVM::new(r"\W")?;
let mut cache = re1.create_cache();
assert_eq!(
Some(Match::must(0, 0..2)),
re1.find_iter(&mut cache, "Δ").next(),
);
// Using 'cache' with re2 is not allowed. It may result in panics or
// incorrect results. In order to re-purpose the cache, we must reset
// it with the PikeVM we'd like to use it with.
//
// Similarly, after this reset, using the cache with 're1' is also not
// allowed.
cache.reset(&re2);
assert_eq!(
Some(Match::must(0, 0..3)),
re2.find_iter(&mut cache, "☃").next(),
);
sourcepub fn memory_usage(&self) -> usize
pub fn memory_usage(&self) -> usize
Returns the heap memory usage, in bytes, of this cache.
This does not include the stack size used up by this cache. To
compute that, use std::mem::size_of::<Cache>()
.
Trait Implementations§
Auto Trait Implementations§
impl Freeze for Cache
impl RefUnwindSafe for Cache
impl Send for Cache
impl Sync for Cache
impl Unpin for Cache
impl UnwindSafe for Cache
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§default unsafe fn clone_to_uninit(&self, dst: *mut T)
default unsafe fn clone_to_uninit(&self, dst: *mut T)
clone_to_uninit
)