pub struct PrefixIterator<T, OnRemoval = ()> { /* private fields */ }
Expand description

Iterate or drain over a prefix and decode raw_key and raw_value into T.

If any decoding fails it skips it and continues to the next key.

If draining, then the hook OnRemoval::on_removal is called after each removal.

Implementations

Creates a new PrefixIterator, iterating after previous_key and filtering out keys that are not prefixed with prefix.

A decode_fn function must also be supplied, and it takes in two &[u8] parameters, returning a Result containing the decoded type T if successful, and a codec::Error on failure. The first &[u8] argument represents the raw, undecoded key without the prefix of the current item, while the second &[u8] argument denotes the corresponding raw, undecoded value.

Get the last key that has been iterated upon and return it.

Get the prefix that is being iterated upon for this iterator and return it.

Set the key that the iterator should start iterating after.

Mutate this iterator into a draining iterator; items iterated are removed from storage.

Trait Implementations

The type of the elements being iterated over.

Advances the iterator and returns the next value. Read more

Returns the bounds on the remaining length of the iterator. Read more

Consumes the iterator, counting the number of iterations and returning it. Read more

Consumes the iterator, returning the last element. Read more

🔬 This is a nightly-only experimental API. (iter_advance_by)

Advances the iterator by n elements. Read more

Returns the nth element of the iterator. Read more

Creates an iterator starting at the same point, but stepping by the given amount at each iteration. Read more

Takes two iterators and creates a new iterator over both in sequence. Read more

‘Zips up’ two iterators into a single iterator of pairs. Read more

🔬 This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places a copy of separator between adjacent items of the original iterator. Read more

🔬 This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator. Read more

Takes a closure and creates an iterator which calls that closure on each element. Read more

Calls a closure on each element of an iterator. Read more

Creates an iterator which uses a closure to determine if an element should be yielded. Read more

Creates an iterator that both filters and maps. Read more

Creates an iterator which gives the current iteration count as well as the next value. Read more

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information. Read more

Creates an iterator that skips elements based on a predicate. Read more

Creates an iterator that yields elements based on a predicate. Read more

Creates an iterator that both yields elements based on a predicate and maps. Read more

Creates an iterator that skips the first n elements. Read more

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner. Read more

An iterator adapter similar to fold that holds internal state and produces a new iterator. Read more

Creates an iterator that works like map, but flattens nested structure. Read more

Creates an iterator that flattens nested structure. Read more

Creates an iterator which ends after the first None. Read more

Does something with each element of an iterator, passing the value on. Read more

Borrows an iterator, rather than consuming it. Read more

Transforms an iterator into a collection. Read more

Consumes an iterator, creating two collections from it. Read more

🔬 This is a nightly-only experimental API. (iter_partition_in_place)

Reorders the elements of this iterator in-place according to the given predicate, such that all those that return true precede all those that return false. Returns the number of true elements found. Read more

🔬 This is a nightly-only experimental API. (iter_is_partitioned)

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false. Read more

An iterator method that applies a function as long as it returns successfully, producing a single, final value. Read more

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error. Read more

Folds every element into an accumulator by applying an operation, returning the final result. Read more

Reduces the elements to a single one, by repeatedly applying a reducing operation. Read more

🔬 This is a nightly-only experimental API. (iterator_try_reduce)

Reduces the elements to a single one by repeatedly applying a reducing operation. If the closure returns a failure, the failure is propagated back to the caller immediately. Read more

Tests if every element of the iterator matches a predicate. Read more

Tests if any element of the iterator matches a predicate. Read more

Searches for an element of an iterator that satisfies a predicate. Read more

Applies function to the elements of iterator and returns the first non-none result. Read more

🔬 This is a nightly-only experimental API. (try_find)

Applies function to the elements of iterator and returns the first true result or the first error. Read more

Searches for an element in an iterator, returning its index. Read more

Searches for an element in an iterator from the right, returning its index. Read more

Returns the maximum element of an iterator. Read more

Returns the minimum element of an iterator. Read more

Returns the element that gives the maximum value from the specified function. Read more

Returns the element that gives the maximum value with respect to the specified comparison function. Read more

Returns the element that gives the minimum value from the specified function. Read more

Returns the element that gives the minimum value with respect to the specified comparison function. Read more

Reverses an iterator’s direction. Read more

Converts an iterator of pairs into a pair of containers. Read more

Creates an iterator which copies all of its elements. Read more

Creates an iterator which clones all of its elements. Read more

Repeats an iterator endlessly. Read more

Sums the elements of an iterator. Read more

Iterates over the entire iterator, multiplying all the elements Read more

Lexicographically compares the elements of this Iterator with those of another. Read more

🔬 This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. Read more

Lexicographically compares the elements of this Iterator with those of another. Read more

🔬 This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. Read more

Determines if the elements of this Iterator are equal to those of another. Read more

🔬 This is a nightly-only experimental API. (iter_order_by)

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function. Read more

Determines if the elements of this Iterator are unequal to those of another. Read more

Determines if the elements of this Iterator are lexicographically less than those of another. Read more

Determines if the elements of this Iterator are lexicographically less or equal to those of another. Read more

Determines if the elements of this Iterator are lexicographically greater than those of another. Read more

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another. Read more

🔬 This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted. Read more

🔬 This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted using the given comparator function. Read more

🔬 This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted using the given key extraction function. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Convert from a value of T into an equivalent instance of Option<Self>. Read more

Consume self to return Some equivalent value of Option<T>. Read more

Convert Box<dyn Trait> (where Trait: Downcast) to Box<dyn Any>. Box<dyn Any> can then be further downcast into Box<ConcreteType> where ConcreteType implements Trait. Read more

Convert Rc<Trait> (where Trait: Downcast) to Rc<Any>. Rc<Any> can then be further downcast into Rc<ConcreteType> where ConcreteType implements Trait. Read more

Convert &Trait (where Trait: Downcast) to &Any. This is needed since Rust cannot generate &Any’s vtable from &Trait’s. Read more

Convert &mut Trait (where Trait: Downcast) to &Any. This is needed since Rust cannot generate &mut Any’s vtable from &mut Trait’s. Read more

Convert Arc<Trait> (where Trait: Downcast) to Arc<Any>. Arc<Any> can then be further downcast into Arc<ConcreteType> where ConcreteType implements Trait. Read more

Performs the conversion.

Instruments this type with the provided Span, returning an Instrumented wrapper. Read more

Instruments this type with the current Span, returning an Instrumented wrapper. Read more

Performs the conversion.

The type of the elements being iterated over.

Which kind of iterator are we turning this into?

Creates an iterator from a value. Read more

Get a reference to the inner from the outer.

Get a mutable reference to the inner from the outer.

Choose one element at random from the iterator. Read more

Choose one element at random from the iterator. Read more

Collects values at random from the iterator into a supplied buffer until that buffer is filled. Read more

Collects amount values at random from the iterator into a vector. Read more

Choose one element at random from the iterator. Read more

Collects values at random from the iterator into a supplied buffer until that buffer is filled. Read more

Collects amount values at random from the iterator into a vector. Read more

Should always be Self

Convert from a value of T into an equivalent instance of Self. Read more

Consume self to return an equivalent value of T. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.

The counterpart to unchecked_from.

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

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

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

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

A transformation which replaces CJK Compatibility Ideograph codepoints with normal forms using Standardized Variation Sequences. This is not part of the canonical or compatibility decomposition algorithms, but performing it before those algorithms produces normalized output which better preserves the intent of the original text. Read more

An Iterator over the string with Conjoining Grapheme Joiner characters inserted according to the Stream-Safe Text Process (UAX15-D4) Read more

Consume self to return an equivalent value of T.

Attaches the provided Subscriber to this type, returning a WithDispatch wrapper. Read more

Attaches the current default Subscriber to this type, returning a WithDispatch wrapper. Read more