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Decoded

Struct Decoded 

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pub struct Decoded(/* private fields */);
Expand description

A CBOR-decoded opaque value descriptor.

A value of this type encapsulates an opaque value descriptor. It cannot be cloned. Dropping it does nothing; this may cause a resource leak, but resource leaks are not considered unsafe Rust, and under the circumstances, closing the descriptor could be unsafe (see the safety note on into_owned for why). The intended use of this type is to immediately call into_owned to convert the value into an Owned instead.

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impl Decoded

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pub unsafe fn into_owned(self) -> Owned

Converts a Decoded descriptor into an Owned descriptor.

§Safety

The caller must ensure that the Decoded descriptor is the only reference to the descriptor it holds, and that that descriptor is valid. Generally, this is accomplished by obtaining a Decoded descriptor by CBOR-decoding the result of a method call, because OC-Wasm guarantees that any opaque value returned from a method call is represented by a fresh descriptor.

The reason why this method is unsafe is that a caller could potentially craft an arbitrary CBOR sequence in a byte buffer, then decode it. If such a decoding operation were to return an Owned directly, this would be unsound, as the caller could decode a second Owned referring to the same descriptor as an existing Owned or an Owned referring to a closed descriptor. Instead, CBOR decoding (which is itself safe) can only create a Decoded, which does not claim exclusive ownership (or even validity) of the contained descriptor but also cannot actually be used as a descriptor; the caller is forced to promise those properties in order to convert to the actually useful Owned type via this unsafe method.

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impl Debug for Decoded

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl<'b, Context> Decode<'b, Context> for Decoded

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fn decode(d: &mut Decoder<'b>, _: &mut Context) -> Result<Self, Error>

Decode a value using the given Decoder. Read more
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fn nil() -> Option<Self>

If possible, return a nil value of Self. Read more
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impl Eq for Decoded

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impl Hash for Decoded

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fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher. Read more
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fn hash_slice<H>(data: &[Self], state: &mut H)
where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl Ord for Decoded

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fn cmp(&self, other: &Decoded) -> Ordering

This method returns an Ordering between self and other. Read more
1.21.0 (const: unstable) · Source§

fn max(self, other: Self) -> Self
where Self: Sized,

Compares and returns the maximum of two values. Read more
1.21.0 (const: unstable) · Source§

fn min(self, other: Self) -> Self
where Self: Sized,

Compares and returns the minimum of two values. Read more
1.50.0 (const: unstable) · Source§

fn clamp(self, min: Self, max: Self) -> Self
where Self: Sized,

Restrict a value to a certain interval. Read more
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impl PartialEq for Decoded

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fn eq(&self, other: &Decoded) -> bool

Tests for self and other values to be equal, and is used by ==.
1.0.0 (const: unstable) · Source§

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl PartialOrd for Decoded

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fn partial_cmp(&self, other: &Decoded) -> Option<Ordering>

This method returns an ordering between self and other values if one exists. Read more
1.0.0 (const: unstable) · Source§

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator. Read more
1.0.0 (const: unstable) · Source§

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator. Read more
1.0.0 (const: unstable) · Source§

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator. Read more
1.0.0 (const: unstable) · Source§

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator. Read more
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impl StructuralPartialEq for Decoded

Auto Trait Implementations§

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.