Struct frame_support::storage::bounded_vec::BoundedVec [−][src]
pub struct BoundedVec<T, S>(_, _);
Expand description
A bounded vector.
It has implementations for efficient append and length decoding, as with a normal Vec<_>
, once
put into storage as a raw value, map or double-map.
As the name suggests, the length of the queue is always bounded. All internal operations ensure this bound is respected.
Implementations
Consume self, and return the inner Vec
. Henceforth, the Vec<_>
can be altered in an
arbitrary way. At some point, if the reverse conversion is required, TryFrom<Vec<_>>
can
be used.
This is useful for cases if you need access to an internal API of the inner Vec<_>
which
is not provided by the wrapper BoundedVec
.
pub fn get_mut<I: SliceIndex<[T]>>(
&mut self,
index: I
) -> Option<&mut <I as SliceIndex<[T]>>::Output>
pub fn get_mut<I: SliceIndex<[T]>>(
&mut self,
index: I
) -> Option<&mut <I as SliceIndex<[T]>>::Output>
Exactly the same semantics as slice::get_mut
.
Consumes self and mutates self via the given mutate
function.
If the outcome of mutation is within bounds, Some(Self)
is returned. Else, None
is
returned.
This is essentially a consuming shorthand Self::into_inner
-> ...
->
Self::try_from
.
Exactly the same semantics as Vec::insert
, but returns an Err
(and is a noop) if the
new length of the vector exceeds S
.
Panics
Panics if index > len
.
Methods from Deref<Target = Vec<T>>
Returns the number of elements the vector can hold without reallocating.
Examples
let vec: Vec<i32> = Vec::with_capacity(10);
assert_eq!(vec.capacity(), 10);
Extracts a slice containing the entire vector.
Equivalent to &s[..]
.
Examples
use std::io::{self, Write};
let buffer = vec![1, 2, 3, 5, 8];
io::sink().write(buffer.as_slice()).unwrap();
Returns a raw pointer to the vector’s buffer.
The caller must ensure that the vector outlives the pointer this function returns, or else it will end up pointing to garbage. Modifying the vector may cause its buffer to be reallocated, which would also make any pointers to it invalid.
The caller must also ensure that the memory the pointer (non-transitively) points to
is never written to (except inside an UnsafeCell
) using this pointer or any pointer
derived from it. If you need to mutate the contents of the slice, use as_mut_ptr
.
Examples
let x = vec![1, 2, 4];
let x_ptr = x.as_ptr();
unsafe {
for i in 0..x.len() {
assert_eq!(*x_ptr.add(i), 1 << i);
}
}
🔬 This is a nightly-only experimental API. (allocator_api
)
allocator_api
)Returns a reference to the underlying allocator.
Returns the number of elements in the vector, also referred to as its ‘length’.
Examples
let a = vec![1, 2, 3];
assert_eq!(a.len(), 3);
Trait Implementations
impl<T, S> Encode for BoundedVec<T, S> where
Vec<T>: Encode,
Vec<T>: Encode,
PhantomData<S>: Encode,
PhantomData<S>: Encode,
impl<T, S> Encode for BoundedVec<T, S> where
Vec<T>: Encode,
Vec<T>: Encode,
PhantomData<S>: Encode,
PhantomData<S>: Encode,
impl<T, S> MaxEncodedLen for BoundedVec<T, S> where
T: MaxEncodedLen,
S: Get<u32>,
BoundedVec<T, S>: Encode,
impl<T, S> MaxEncodedLen for BoundedVec<T, S> where
T: MaxEncodedLen,
S: Get<u32>,
BoundedVec<T, S>: Encode,
Upper bound, in bytes, of the maximum encoded size of this item.
impl<T, S> TypeInfo for BoundedVec<T, S> where
Vec<T>: TypeInfo + 'static,
PhantomData<S>: TypeInfo + 'static,
T: TypeInfo + 'static,
S: 'static,
impl<T, S> TypeInfo for BoundedVec<T, S> where
Vec<T>: TypeInfo + 'static,
PhantomData<S>: TypeInfo + 'static,
T: TypeInfo + 'static,
S: 'static,
impl<T, S> EncodeLike<BoundedVec<T, S>> for BoundedVec<T, S> where
Vec<T>: Encode,
Vec<T>: Encode,
PhantomData<S>: Encode,
PhantomData<S>: Encode,
impl<'a, T: Encode + Decode, S: Get<u32>> EncodeLike<BoundedVec<T, S>> for BoundedSlice<'a, T, S>
Auto Trait Implementations
impl<T, S> RefUnwindSafe for BoundedVec<T, S> where
S: RefUnwindSafe,
T: RefUnwindSafe,
impl<T, S> Send for BoundedVec<T, S> where
S: Send,
T: Send,
impl<T, S> Sync for BoundedVec<T, S> where
S: Sync,
T: Sync,
impl<T, S> Unpin for BoundedVec<T, S> where
S: Unpin,
T: Unpin,
impl<T, S> UnwindSafe for BoundedVec<T, S> where
S: UnwindSafe,
T: UnwindSafe,
Blanket Implementations
Views memory as a slice of mutable bits. Read more
Mutably borrows from an owned value. 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
Compare self to key
and return true
if they are equal.
Causes self
to use its Binary
implementation when Debug
-formatted.
Causes self
to use its Display
implementation when
Debug
-formatted. Read more
Causes self
to use its LowerExp
implementation when
Debug
-formatted. Read more
Causes self
to use its LowerHex
implementation when
Debug
-formatted. Read more
Causes self
to use its Octal
implementation when Debug
-formatted.
Causes self
to use its Pointer
implementation when
Debug
-formatted. Read more
Causes self
to use its UpperExp
implementation when
Debug
-formatted. Read more
Causes self
to use its UpperHex
implementation when
Debug
-formatted. Read more
Pipes by value. This is generally the method you want to use. Read more
Borrows self
and passes that borrow into the pipe function. Read more
Mutably borrows self
and passes that borrow into the pipe function. Read more
Borrows self
, then passes self.borrow()
into the pipe function. Read more
Mutably borrows self
, then passes self.borrow_mut()
into the pipe
function. Read more
Borrows self
, then passes self.as_ref()
into the pipe function.
Mutably borrows self
, then passes self.as_mut()
into the pipe
function. Read more
Borrows self
, then passes self.deref()
into the pipe function.
fn pipe_as_ref<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: AsRef<T>,
T: 'a,
R: 'a,
fn pipe_as_ref<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: AsRef<T>,
T: 'a,
R: 'a,
Pipes a trait borrow into a function that cannot normally be called in suffix position. Read more
fn pipe_borrow<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: Borrow<T>,
T: 'a,
R: 'a,
fn pipe_borrow<'a, T, R>(&'a self, func: impl FnOnce(&'a T) -> R) -> R where
Self: Borrow<T>,
T: 'a,
R: 'a,
Pipes a trait borrow into a function that cannot normally be called in suffix position. Read more
fn pipe_deref<'a, R>(&'a self, func: impl FnOnce(&'a Self::Target) -> R) -> R where
Self: Deref,
R: 'a,
fn pipe_deref<'a, R>(&'a self, func: impl FnOnce(&'a Self::Target) -> R) -> R where
Self: Deref,
R: 'a,
Pipes a dereference into a function that cannot normally be called in suffix position. Read more
Pipes a reference into a function that cannot ordinarily be called in suffix position. Read more
Immutable access to the Borrow<B>
of a value. Read more
Mutable access to the BorrowMut<B>
of a value. Read more
Immutable access to the AsRef<R>
view of a value. Read more
Mutable access to the AsMut<R>
view of a value. Read more
Immutable access to the Deref::Target
of a value. Read more
Mutable access to the Deref::Target
of a value. Read more
Calls .tap()
only in debug builds, and is erased in release builds.
Calls .tap_mut()
only in debug builds, and is erased in release
builds. Read more
Calls .tap_borrow()
only in debug builds, and is erased in release
builds. Read more
Calls .tap_borrow_mut()
only in debug builds, and is erased in release
builds. Read more
Calls .tap_ref()
only in debug builds, and is erased in release
builds. Read more
Calls .tap_ref_mut()
only in debug builds, and is erased in release
builds. Read more
Calls .tap_deref()
only in debug builds, and is erased in release
builds. Read more
Provides immutable access to the reference for inspection.
Calls tap_ref
in debug builds, and does nothing in release builds.
Provides mutable access to the reference for modification.
Calls tap_ref_mut
in debug builds, and does nothing in release builds.
Provides immutable access to the borrow for inspection. Read more
Calls tap_borrow
in debug builds, and does nothing in release builds.
fn tap_borrow_mut<F, R>(self, func: F) -> Self where
Self: BorrowMut<T>,
F: FnOnce(&mut T) -> R,
fn tap_borrow_mut<F, R>(self, func: F) -> Self where
Self: BorrowMut<T>,
F: FnOnce(&mut T) -> R,
Provides mutable access to the borrow for modification.
Immutably dereferences self
for inspection.
fn tap_deref_dbg<F, R>(self, func: F) -> Self where
Self: Deref,
F: FnOnce(&Self::Target) -> R,
fn tap_deref_dbg<F, R>(self, func: F) -> Self where
Self: Deref,
F: FnOnce(&Self::Target) -> R,
Calls tap_deref
in debug builds, and does nothing in release builds.
fn tap_deref_mut<F, R>(self, func: F) -> Self where
Self: DerefMut,
F: FnOnce(&mut Self::Target) -> R,
fn tap_deref_mut<F, R>(self, func: F) -> Self where
Self: DerefMut,
F: FnOnce(&mut Self::Target) -> R,
Mutably dereferences self
for modification.
The counterpart to unchecked_from
.
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