<main><divclass="width-limiter"><navclass="sub"><formclass="search-form"><span></span><divid="sidebar-button"tabindex="-1"><ahref="../../../regex_automata/all.html"title="show sidebar"></a></div><inputclass="search-input"name="search"aria-label="Run search in the documentation"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><divid="help-button"tabindex="-1"><ahref="../../../help.html"title="help">?</a></div><divid="settings-menu"tabindex="-1"><ahref="../../../settings.html"title="settings"><imgwidth="22"height="22"alt="Change settings"src="../../../static.files/wheel-7b819b6101059cd0.svg"></a></div></form></nav><sectionid="main-content"class="content"><divclass="main-heading"><h1>Struct <ahref="../../index.html">regex_automata</a>::<wbr><ahref="../index.html">hybrid</a>::<wbr><ahref="index.html">dfa</a>::<wbr><aclass="struct"href="#">Cache</a><buttonid="copy-path"title="Copy item path to clipboard"><imgsrc="../../../static.files/clipboard-7571035ce49a181d.svg"width="19"height="18"alt="Copy item path"></button></h1><spanclass="out-of-band"><aclass="src"href="../../../src/regex_automata/hybrid/dfa.rs.html#1777-1867">source</a> · <buttonid="toggle-all-docs"title="collapse all docs">[<span>−</span>]</button></span></div><preclass="rust item-decl"><code>pub struct Cache { <spanclass="comment">/* private fields */</span> }</code></pre><detailsclass="toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>A cache represents a partially computed DFA.</p>
<p>A cache is the key component that differentiates a classical DFA and a
hybrid NFA/DFA (also called a “lazy DFA”). Where a classical DFA builds a
complete transition table that can handle all possible inputs, a hybrid
NFA/DFA starts with an empty transition table and builds only the parts
required during search. The parts that are built are stored in a cache. For
this reason, a cache is a required parameter for nearly every operation on
a <ahref="struct.DFA.html"title="struct regex_automata::hybrid::dfa::DFA"><code>DFA</code></a>.</p>
<p>Caches can be created from their corresponding DFA via
<ahref="struct.DFA.html#method.create_cache"title="method regex_automata::hybrid::dfa::DFA::create_cache"><code>DFA::create_cache</code></a>. A cache can only be used with either the DFA that
created it, or the DFA that was most recently used to reset it with
<ahref="struct.Cache.html#method.reset"title="method regex_automata::hybrid::dfa::Cache::reset"><code>Cache::reset</code></a>. Using a cache with any other DFA may result in panics
or incorrect results.</p>
</div></details><h2id="implementations"class="section-header">Implementations<ahref="#implementations"class="anchor">§</a></h2><divid="implementations-list"><detailsclass="toggle implementors-toggle"open><summary><sectionid="impl-Cache"class="impl"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#1869-2039">source</a><ahref="#impl-Cache"class="anchor">§</a><h3class="code-header">impl <aclass="struct"href="struct.Cache.html"title="struct regex_automata::hybrid::dfa::Cache">Cache</a></h3></section></summary><divclass="impl-items"><detailsclass="toggle method-toggle"open><summary><sectionid="method.new"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#1875-1894">source</a><h4class="code-header">pub fn <ahref="#method.new"class="fn">new</a>(dfa: &<aclass="struct"href="struct.DFA.html"title="struct regex_automata::hybrid::dfa::DFA">DFA</a>) -><aclass="struct"href="struct.Cache.html"title="struct regex_automata::hybrid::dfa::Cache">Cache</a></h4></section></summary><divclass="docblock"><p>Create a new cache for the given lazy DFA.</p>
<p>The cache returned should only be used for searches for the given DFA.
If you want to reuse the cache for another DFA, then you must call
<ahref="struct.Cache.html#method.reset"title="method regex_automata::hybrid::dfa::Cache::reset"><code>Cache::reset</code></a> with that DFA.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.reset"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#1940-1942">source</a><h4class="code-header">pub fn <ahref="#method.reset"class="fn">reset</a>(&mut self, dfa: &<aclass="struct"href="struct.DFA.html"title="struct regex_automata::hybrid::dfa::DFA">DFA</a>)</h4></section></summary><divclass="docblock"><p>Reset this cache such that it can be used for searching with the given
lazy DFA (and only that DFA).</p>
<p>A cache reset permits reusing memory already allocated in this cache
with a different lazy DFA.</p>
<p>Resetting a cache sets its “clear count” to 0. This is relevant if the
lazy DFA has been configured to “give up” after it has cleared the
cache a certain number of times.</p>
<p>Any lazy state ID generated by the cache prior to resetting it is
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.search_start"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#1954-1961">source</a><h4class="code-header">pub fn <ahref="#method.search_start"class="fn">search_start</a>(&mut self, at: <aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>)</h4></section></summary><divclass="docblock"><p>Initializes a new search starting at the given position.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.search_update"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#1973-1977">source</a><h4class="code-header">pub fn <ahref="#method.search_update"class="fn">search_update</a>(&mut self, at: <aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>)</h4></section></summary><divclass="docblock"><p>Updates the current search to indicate that it has search to the
<p>This panics if no search has been started by <ahref="struct.Cache.html#method.search_start"title="method regex_automata::hybrid::dfa::Cache::search_start"><code>Cache::search_start</code></a>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.search_finish"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#1985-1990">source</a><h4class="code-header">pub fn <ahref="#method.search_finish"class="fn">search_finish</a>(&mut self, at: <aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a>)</h4></section></summary><divclass="docblock"><p>Indicates that a search has finished at the given position.</p>
<p>This panics if no search has been started by <ahref="struct.Cache.html#method.search_start"title="method regex_automata::hybrid::dfa::Cache::search_start"><code>Cache::search_start</code></a>.</p>
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.search_total_len"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#2003-2005">source</a><h4class="code-header">pub fn <ahref="#method.search_total_len"class="fn">search_total_len</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>Returns the total number of bytes that have been searched since this
<p>This is useful for determining the efficiency of the cache. For
example, the lazy DFA uses this value in conjunction with the
<ahref="struct.Config.html#method.minimum_bytes_per_state"title="method regex_automata::hybrid::dfa::Config::minimum_bytes_per_state"><code>Config::minimum_bytes_per_state</code></a> knob to help determine whether it
should quit searching.</p>
<p>This always returns <code>0</code> if search progress isn’t being tracked. Note
that the lazy DFA search routines in this crate always track search
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.clear_count"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#2013-2015">source</a><h4class="code-header">pub fn <ahref="#method.clear_count"class="fn">clear_count</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>Returns the total number of times this cache has been cleared since it
</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.memory_usage"class="method"><aclass="src rightside"href="../../../src/regex_automata/hybrid/dfa.rs.html#2021-2038">source</a><h4class="code-header">pub fn <ahref="#method.memory_usage"class="fn">memory_usage</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.usize.html">usize</a></h4></section></summary><divclass="docblock"><p>Returns the heap memory usage, in bytes, of this cache.</p>
<code><ahref="https://doc.rust-lang.org/1.77.1/core/convert/trait.From.html"title="trait core::convert::From">From</a><T> for U</code> chooses to do.</p>
</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-ToOwned-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/alloc/borrow.rs.html#83-85">source</a><ahref="#impl-ToOwned-for-T"class="anchor">§</a><h3class="code-header">impl<T><aclass="trait"href="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html"title="trait alloc::borrow::ToOwned">ToOwned</a> for T<divclass="where">where
T: <aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/clone/trait.Clone.html"title="trait core::clone::Clone">Clone</a>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Owned"class="associatedtype trait-impl"><ahref="#associatedtype.Owned"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#associatedtype.Owned"class="associatedtype">Owned</a> = T</h4></section></summary><divclass='docblock'>The resulting type after obtaining ownership.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.to_owned"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/alloc/borrow.rs.html#88">source</a><ahref="#method.to_owned"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#tymethod.to_owned"class="fn">to_owned</a>(&self) -> T</h4></section></summary><divclass='docblock'>Creates owned data from borrowed data, usually by cloning. <ahref="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#tymethod.to_owned">Read more</a></div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.clone_into"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/alloc/borrow.rs.html#92">source</a><ahref="#method.clone_into"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#method.clone_into"class="fn">clone_into</a>(&self, target: <aclass="primitive"href="https://doc.rust-lang.org/1.77.1/std/primitive.reference.html">&mut T</a>)</h4></section></summary><divclass='docblock'>Uses borrowed data to replace owned data, usually by cloning. <ahref="https://doc.rust-lang.org/1.77.1/alloc/borrow/trait.ToOwned.html#method.clone_into">Read more</a></div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryFrom%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#804-806">source</a><ahref="#impl-TryFrom%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error-1"class="associatedtype trait-impl"><ahref="#associatedtype.Error-1"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="enum"href="https://doc.rust-lang.org/1.77.1/core/convert/enum.Infallible.html"title="enum core::convert::Infallible">Infallible</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_from"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#811">source</a><ahref="#method.try_from"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html#tymethod.try_from"class="fn">try_from</a>(value: U) -><aclass="enum"href="https://doc.rust-lang.org/1.77.1/core/result/enum.Result.html"title="enum core::result::Result">Result</a><T, <T as <aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details><detailsclass="toggle implementors-toggle"><summary><sectionid="impl-TryInto%3CU%3E-for-T"class="impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#789-791">source</a><ahref="#impl-TryInto%3CU%3E-for-T"class="anchor">§</a><h3class="code-header">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryInto.html"title="trait core::convert::TryInto">TryInto</a><U> for T<divclass="where">where
U: <aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>,</div></h3></section></summary><divclass="impl-items"><detailsclass="toggle"open><summary><sectionid="associatedtype.Error"class="associatedtype trait-impl"><ahref="#associatedtype.Error"class="anchor">§</a><h4class="code-header">type <ahref="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryInto.html#associatedtype.Error"class="associatedtype">Error</a> = <U as <aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><divclass='docblock'>The type returned in the event of a conversion error.</div></details><detailsclass="toggle method-toggle"open><summary><sectionid="method.try_into"class="method trait-impl"><aclass="src rightside"href="https://doc.rust-lang.org/1.77.1/src/core/convert/mod.rs.html#796">source</a><ahref="#method.try_into"class="anchor">§</a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryInto.html#tymethod.try_into"class="fn">try_into</a>(self) -><aclass="enum"href="https://doc.rust-lang.org/1.77.1/core/result/enum.Result.html"title="enum core::result::Result">Result</a><U, <U as <aclass="trait"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/1.77.1/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a>></h4></section></summary><divclass='docblock'>Performs the conversion.</div></details></div></details></div></section></div></main></body></html>
