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DescriptorFlags

Struct DescriptorFlags 

pub struct DescriptorFlags(<DescriptorFlags as PublicFlags>::Internal);
Expand description

Flags for a GDT descriptor. Not all flags are valid for all descriptor types.

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§0: <DescriptorFlags as PublicFlags>::Internal

Implementations§

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impl DescriptorFlags

pub const ACCESSED: DescriptorFlags

Set by the processor if this segment has been accessed. Only cleared by software. Setting this bit in software prevents GDT writes on first use.

pub const WRITABLE: DescriptorFlags

For 32-bit data segments, sets the segment as writable. For 32-bit code segments, sets the segment as readable. In 64-bit mode, ignored for all segments.

pub const CONFORMING: DescriptorFlags

For code segments, sets the segment as “conforming”, influencing the privilege checks that occur on control transfers. For 32-bit data segments, sets the segment as “expand down”. In 64-bit mode, ignored for data segments.

pub const EXECUTABLE: DescriptorFlags

This flag must be set for code segments and unset for data segments.

pub const USER_SEGMENT: DescriptorFlags

This flag must be set for user segments (in contrast to system segments).

pub const DPL_RING_3: DescriptorFlags

These two bits encode the Descriptor Privilege Level (DPL) for this descriptor. If both bits are set, the DPL is Ring 3, if both are unset, the DPL is Ring 0.

pub const PRESENT: DescriptorFlags

Must be set for any segment, causes a segment not present exception if not set.

pub const AVAILABLE: DescriptorFlags

Available for use by the Operating System

pub const LONG_MODE: DescriptorFlags

Must be set for 64-bit code segments, unset otherwise.

pub const DEFAULT_SIZE: DescriptorFlags

Use 32-bit (as opposed to 16-bit) operands. If LONG_MODE is set, this must be unset. In 64-bit mode, ignored for data segments.

pub const GRANULARITY: DescriptorFlags

Limit field is scaled by 4096 bytes. In 64-bit mode, ignored for all segments.

pub const LIMIT_0_15: DescriptorFlags

Bits 0..=15 of the limit field (ignored in 64-bit mode)

pub const LIMIT_16_19: DescriptorFlags

Bits 16..=19 of the limit field (ignored in 64-bit mode)

pub const BASE_0_23: DescriptorFlags

Bits 0..=23 of the base field (ignored in 64-bit mode, except for fs and gs)

pub const BASE_24_31: DescriptorFlags

Bits 24..=31 of the base field (ignored in 64-bit mode, except for fs and gs)

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impl DescriptorFlags

pub const fn empty() -> DescriptorFlags

Get a flags value with all bits unset.

pub const fn all() -> DescriptorFlags

Get a flags value with all known bits set.

pub const fn bits(&self) -> u64

Get the underlying bits value.

The returned value is exactly the bits set in this flags value.

pub const fn from_bits(bits: u64) -> Option<DescriptorFlags>

Convert from a bits value.

This method will return None if any unknown bits are set.

pub const fn from_bits_truncate(bits: u64) -> DescriptorFlags

Convert from a bits value, unsetting any unknown bits.

pub const fn from_bits_retain(bits: u64) -> DescriptorFlags

Convert from a bits value exactly.

pub fn from_name(name: &str) -> Option<DescriptorFlags>

Get a flags value with the bits of a flag with the given name set.

This method will return None if name is empty or doesn’t correspond to any named flag.

pub const fn is_empty(&self) -> bool

Whether all bits in self are unset.

pub const fn is_all(&self) -> bool

Whether all known bits in this flags value are set.

pub const fn intersects(&self, other: DescriptorFlags) -> bool

Whether any set bits in other are also set in self.

pub const fn contains(&self, other: DescriptorFlags) -> bool

Whether all set bits in other are also set in self.

pub fn insert(&mut self, other: DescriptorFlags)

The bitwise or (|) of the bits in self and other.

pub fn remove(&mut self, other: DescriptorFlags)

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. remove won’t truncate other, but the ! operator will.

pub fn toggle(&mut self, other: DescriptorFlags)

The bitwise exclusive-or (^) of the bits in self and other.

pub fn set(&mut self, other: DescriptorFlags, value: bool)

Call insert when value is true or remove when value is false.

pub const fn intersection(self, other: DescriptorFlags) -> DescriptorFlags

The bitwise and (&) of the bits in self and other.

pub const fn union(self, other: DescriptorFlags) -> DescriptorFlags

The bitwise or (|) of the bits in self and other.

pub const fn difference(self, other: DescriptorFlags) -> DescriptorFlags

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

pub const fn symmetric_difference( self, other: DescriptorFlags, ) -> DescriptorFlags

The bitwise exclusive-or (^) of the bits in self and other.

pub const fn complement(self) -> DescriptorFlags

The bitwise negation (!) of the bits in self, truncating the result.

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impl DescriptorFlags

pub const fn iter(&self) -> Iter<DescriptorFlags> ⓘ

Yield a set of contained flags values.

Each yielded flags value will correspond to a defined named flag. Any unknown bits will be yielded together as a final flags value.

pub const fn iter_names(&self) -> IterNames<DescriptorFlags> ⓘ

Yield a set of contained named flags values.

This method is like iter, except only yields bits in contained named flags. Any unknown bits, or bits not corresponding to a contained flag will not be yielded.

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impl DescriptorFlags

The following constants define default values for common GDT entries. They are all “flat” segments, meaning they can access the entire address space. These values all set WRITABLE and ACCESSED. They also match the values loaded by the syscall/sysret and sysenter/sysexit instructions.

In short, these values disable segmentation, permission checks, and access tracking at the GDT level. Kernels using these values should use paging to implement this functionality.

pub const KERNEL_DATA: DescriptorFlags

A kernel data segment (64-bit or flat 32-bit)

pub const KERNEL_CODE32: DescriptorFlags

A flat 32-bit kernel code segment

pub const KERNEL_CODE64: DescriptorFlags

A 64-bit kernel code segment

pub const USER_DATA: DescriptorFlags

A user data segment (64-bit or flat 32-bit)

pub const USER_CODE32: DescriptorFlags

A flat 32-bit user code segment

pub const USER_CODE64: DescriptorFlags

A 64-bit user code segment

Trait Implementations§

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impl Binary for DescriptorFlags

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

Formats the value using the given formatter. Read more
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impl BitAnd for DescriptorFlags

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fn bitand(self, other: DescriptorFlags) -> DescriptorFlags

The bitwise and (&) of the bits in self and other.

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type Output = DescriptorFlags

The resulting type after applying the & operator.
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impl BitAndAssign for DescriptorFlags

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fn bitand_assign(&mut self, other: DescriptorFlags)

The bitwise and (&) of the bits in self and other.

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impl BitOr for DescriptorFlags

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fn bitor(self, other: DescriptorFlags) -> DescriptorFlags

The bitwise or (|) of the bits in self and other.

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type Output = DescriptorFlags

The resulting type after applying the | operator.
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impl BitOrAssign for DescriptorFlags

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fn bitor_assign(&mut self, other: DescriptorFlags)

The bitwise or (|) of the bits in self and other.

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impl BitXor for DescriptorFlags

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fn bitxor(self, other: DescriptorFlags) -> DescriptorFlags

The bitwise exclusive-or (^) of the bits in self and other.

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type Output = DescriptorFlags

The resulting type after applying the ^ operator.
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impl BitXorAssign for DescriptorFlags

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fn bitxor_assign(&mut self, other: DescriptorFlags)

The bitwise exclusive-or (^) of the bits in self and other.

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impl Clone for DescriptorFlags

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fn clone(&self) -> DescriptorFlags

Returns a duplicate of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Copy for DescriptorFlags

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impl Debug for DescriptorFlags

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

Formats the value using the given formatter. Read more
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impl Eq for DescriptorFlags

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impl Extend<DescriptorFlags> for DescriptorFlags

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fn extend<T>(&mut self, iterator: T)
where T: IntoIterator<Item = DescriptorFlags>,

The bitwise or (|) of the bits in each flags value.

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fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)
Extends a collection with exactly one element.
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fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)
Reserves capacity in a collection for the given number of additional elements. Read more
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impl Flags for DescriptorFlags

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const FLAGS: &'static [Flag<DescriptorFlags>]

The set of defined flags.
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type Bits = u64

The underlying bits type.
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fn bits(&self) -> u64

Get the underlying bits value. Read more
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fn from_bits_retain(bits: u64) -> DescriptorFlags

Convert from a bits value exactly.
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fn all_named() -> DescriptorFlags

Get a flags value with all bits from named flags set. Read more
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fn empty() -> Self

Get a flags value with all bits unset.
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fn all() -> Self

Get a flags value with all known bits set.
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fn known_bits(&self) -> Self::Bits

Get the known bits from a flags value.
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fn unknown_bits(&self) -> Self::Bits

Get the unknown bits from a flags value.
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fn contains_unknown_bits(&self) -> bool

This method will return true if any unknown bits are set.
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fn from_bits(bits: Self::Bits) -> Option<Self>

Convert from a bits value. Read more
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fn from_bits_truncate(bits: Self::Bits) -> Self

Convert from a bits value, unsetting any unknown bits.
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fn from_name(name: &str) -> Option<Self>

Get a flags value with the bits of a flag with the given name set. Read more
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fn iter(&self) -> Iter<Self> ⓘ

Yield a set of contained flags values. Read more
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fn iter_names(&self) -> IterNames<Self> ⓘ

Yield a set of contained named flags values. Read more
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fn iter_defined_names() -> IterDefinedNames<Self> ⓘ

Yield a set of all named flags defined by [Self::FLAGS].
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fn iter_equal_names(&self) -> IterEqualNames<Self> ⓘ

Get an iterator over all defined names for this flags value. Read more
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fn is_empty(&self) -> bool

Whether all bits in this flags value are unset.
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fn is_all(&self) -> bool

Whether all known bits in this flags value are set.
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fn intersects(&self, other: Self) -> bool
where Self: Sized,

Whether any set bits in other are also set in self.
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fn contains(&self, other: Self) -> bool
where Self: Sized,

Whether all set bits in other are also set in self.
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fn truncate(&mut self)
where Self: Sized,

Remove any unknown bits from the flags.
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fn insert(&mut self, other: Self)
where Self: Sized,

The bitwise or (|) of the bits in self and other.
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fn remove(&mut self, other: Self)
where Self: Sized,

The intersection of self with the complement of other (&!). Read more
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fn toggle(&mut self, other: Self)
where Self: Sized,

The bitwise exclusive-or (^) of the bits in self and other.
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fn set(&mut self, other: Self, value: bool)
where Self: Sized,

Call [Flags::insert] when value is true or [Flags::remove] when value is false.
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fn clear(&mut self)
where Self: Sized,

Unsets all bits in the flags.
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fn intersection(self, other: Self) -> Self

The bitwise and (&) of the bits in self and other.
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fn union(self, other: Self) -> Self

The bitwise or (|) of the bits in self and other.
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fn difference(self, other: Self) -> Self

The intersection of self with the complement of other (&!). Read more
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fn symmetric_difference(self, other: Self) -> Self

The bitwise exclusive-or (^) of the bits in self and other.
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fn complement(self) -> Self

The bitwise negation (!) of the bits in self, truncating the result.
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impl FromIterator<DescriptorFlags> for DescriptorFlags

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fn from_iter<T>(iterator: T) -> DescriptorFlags
where T: IntoIterator<Item = DescriptorFlags>,

The bitwise or (|) of the bits in each flags value.

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impl Hash for DescriptorFlags

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

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 IntoIterator for DescriptorFlags

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type Item = DescriptorFlags

The type of the elements being iterated over.
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type IntoIter = Iter<DescriptorFlags>

Which kind of iterator are we turning this into?
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fn into_iter(self) -> <DescriptorFlags as IntoIterator>::IntoIter

Creates an iterator from a value. Read more
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impl LowerHex for DescriptorFlags

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

Formats the value using the given formatter. Read more
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impl Not for DescriptorFlags

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fn not(self) -> DescriptorFlags

The bitwise negation (!) of the bits in self, truncating the result.

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type Output = DescriptorFlags

The resulting type after applying the ! operator.
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impl Octal for DescriptorFlags

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

Formats the value using the given formatter. Read more
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impl Ord for DescriptorFlags

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fn cmp(&self, other: &DescriptorFlags) -> 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
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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 DescriptorFlags

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

Equality operator ==. Read more
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fn ne(&self, other: &Rhs) -> bool

Inequality operator !=. Read more
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impl PartialOrd for DescriptorFlags

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

This method returns an ordering between self and other values if one exists. Read more
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fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator. Read more
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fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator. Read more
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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 DescriptorFlags

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impl Sub for DescriptorFlags

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fn sub(self, other: DescriptorFlags) -> DescriptorFlags

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

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type Output = DescriptorFlags

The resulting type after applying the - operator.
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impl SubAssign for DescriptorFlags

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fn sub_assign(&mut self, other: DescriptorFlags)

The intersection of self with the complement of other (&!).

This method is not equivalent to self & !other when other has unknown bits set. difference won’t truncate other, but the ! operator will.

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impl UpperHex for DescriptorFlags

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

Formats the value using the given formatter. Read more

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Mutably borrows from an owned value. Read more
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unsafe fn clone_to_uninit(&self, dest: *mut u8)

🔬This is a nightly-only experimental API. (clone_to_uninit)
Performs copy-assignment from self to dest. Read more
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impl<Q, K> Comparable<K> for Q
where Q: Ord + ?Sized, K: Borrow<Q> + ?Sized,

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fn compare(&self, key: &K) -> Ordering

Compare self to key and return their ordering.
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Compare self to key and return true if they are equal.
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Returns the argument unchanged.

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Calls U::from(self).

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Converts self into a Left variant of Either<Self, Self> if into_left is true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
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where F: FnOnce(&Self) -> bool,

Converts self into a Left variant of Either<Self, Self> if into_left(&self) returns true. Converts self into a Right variant of Either<Self, Self> otherwise. Read more
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