Struct WriteFlags

pub struct WriteFlags { /* private fields */ }

Write options.

Implementations

impl WriteFlags

pub const NO_OVERWRITE: Self = _

Insert the new item only if the key does not already appear in the database. The function will return LmdbError::KeyExist if the key already appears in the database, even if the database supports duplicates (DUP_SORT).

pub const NO_DUP_DATA: Self = _

Insert the new item only if it does not already appear in the database. This flag may only be specified if the database was opened with DUP_SORT. The function will return LmdbError::KeyExist if the item already appears in the database.

pub const CURRENT: Self = _

For Cursor::put. Replace the item at the current cursor position. The key parameter must match the current position. If using sorted duplicates (DUP_SORT) the data item must still sort into the same position. This is intended to be used when the new data is the same size as the old. Otherwise it will simply perform a delete of the old record followed by an insert.

pub const APPEND: Self = _

Append the given item to the end of the database. No key comparisons are performed. This option allows fast bulk loading when keys are already known to be in the correct order. Loading unsorted keys with this flag will cause data corruption.

pub const APPEND_DUP: Self = _

Same as APPEND, but for sorted dup data.

pub const fn empty() -> Self

Returns an empty set of flags.

pub const fn all() -> Self

Returns the set containing all flags.

pub const fn bits(&self) -> c_uint

Returns the raw value of the flags currently stored.

pub const fn from_bits(bits: c_uint) -> Option<Self>

Convert from underlying bit representation, unless that representation contains bits that do not correspond to a flag.

pub const fn from_bits_truncate(bits: c_uint) -> Self

Convert from underlying bit representation, dropping any bits that do not correspond to flags.

pub const unsafe fn from_bits_unchecked(bits: c_uint) -> Self

Convert from underlying bit representation, preserving all bits (even those not corresponding to a defined flag).

Safety

The caller of the bitflags! macro can chose to allow or disallow extra bits for their bitflags type.

The caller of from_bits_unchecked() has to ensure that all bits correspond to a defined flag or that extra bits are valid for this bitflags type.

pub const fn is_empty(&self) -> bool

Returns true if no flags are currently stored.

pub const fn is_all(&self) -> bool

Returns true if all flags are currently set.

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

Returns true if there are flags common to both self and other.

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

Returns true if all of the flags in other are contained within self.

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

Inserts the specified flags in-place.

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

Removes the specified flags in-place.

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

Toggles the specified flags in-place.

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

Inserts or removes the specified flags depending on the passed value.

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

Returns the intersection between the flags in self and other.

Specifically, the returned set contains only the flags which are present in both self and other.

This is equivalent to using the & operator (e.g. ops::BitAnd), as in flags & other.

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

Returns the union of between the flags in self and other.

Specifically, the returned set contains all flags which are present in either self or other, including any which are present in both (see Self::symmetric_difference if that is undesirable).

This is equivalent to using the | operator (e.g. ops::BitOr), as in flags | other.

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

Returns the difference between the flags in self and other.

Specifically, the returned set contains all flags present in self, except for the ones present in other.

It is also conceptually equivalent to the “bit-clear” operation: flags & !other (and this syntax is also supported).

This is equivalent to using the - operator (e.g. ops::Sub), as in flags - other.

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

Returns the symmetric difference between the flags in self and other.

Specifically, the returned set contains the flags present which are present in self or other, but that are not present in both. Equivalently, it contains the flags present in exactly one of the sets self and other.

This is equivalent to using the ^ operator (e.g. ops::BitXor), as in flags ^ other.

pub const fn complement(self) -> Self

Returns the complement of this set of flags.

Specifically, the returned set contains all the flags which are not set in self, but which are allowed for this type.

Alternatively, it can be thought of as the set difference between Self::all() and self (e.g. Self::all() - self)

This is equivalent to using the ! operator (e.g. ops::Not), as in !flags.

Trait Implementations

impl Binary for WriteFlags

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

Formats the value using the given formatter.

impl BitAnd for WriteFlags

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

Returns the intersection between the two sets of flags.

type Output = WriteFlags

The resulting type after applying the & operator.

impl BitAndAssign for WriteFlags

fn bitand_assign(&mut self, other: Self)

Disables all flags disabled in the set.

impl BitOr for WriteFlags

fn bitor(self, other: WriteFlags) -> Self

Returns the union of the two sets of flags.

type Output = WriteFlags

The resulting type after applying the | operator.

impl BitOrAssign for WriteFlags

fn bitor_assign(&mut self, other: Self)

Adds the set of flags.

impl BitXor for WriteFlags

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

Returns the left flags, but with all the right flags toggled.

type Output = WriteFlags

The resulting type after applying the ^ operator.

impl BitXorAssign for WriteFlags

fn bitxor_assign(&mut self, other: Self)

Toggles the set of flags.

impl Clone for WriteFlags

fn clone(&self) -> WriteFlags

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WriteFlags

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

Formats the value using the given formatter.

impl Default for WriteFlags

fn default() -> WriteFlags

Returns the “default value” for a type.

impl Extend<WriteFlags> for WriteFlags

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

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

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

Extends a collection with exactly one element.

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.

impl FromIterator<WriteFlags> for WriteFlags

fn from_iter<T: IntoIterator<Item = Self>>(iterator: T) -> Self

Creates a value from an iterator.

impl Hash for WriteFlags

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

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl LowerHex for WriteFlags

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

Formats the value using the given formatter.

impl Not for WriteFlags

fn not(self) -> Self

Returns the complement of this set of flags.

type Output = WriteFlags

The resulting type after applying the ! operator.

impl Octal for WriteFlags

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

Formats the value using the given formatter.

impl Ord for WriteFlags

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

This method returns an Ordering between self and other.

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

where Self: Sized,

Compares and returns the maximum of two values.

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

where Self: Sized,

Compares and returns the minimum of two values.

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

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for WriteFlags

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

Tests for self and other values to be equal, and is used by ==.

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

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

impl PartialOrd for WriteFlags

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

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

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

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

Tests greater than (for self and other) and is used by the > operator.

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

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

impl Sub for WriteFlags

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

Returns the set difference of the two sets of flags.

type Output = WriteFlags

The resulting type after applying the - operator.

impl SubAssign for WriteFlags

fn sub_assign(&mut self, other: Self)

Disables all flags enabled in the set.

impl UpperHex for WriteFlags

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

Formats the value using the given formatter.

impl Copy for WriteFlags

impl Eq for WriteFlags

impl StructuralPartialEq for WriteFlags