Struct frame_support::storage::types::OptionQuery
source · pub struct OptionQuery;
Expand description
Implement QueryKindTrait with query being Option<Value>
NOTE: it doesn’t support a generic OnEmpty
. This means only None
can be
returned when no value is found. To use another OnEmpty
implementation, ValueQuery
can be
used instead.
Trait Implementations§
source§impl<Value> QueryKindTrait<Value, GetDefault> for OptionQuerywhere
Value: FullCodec + 'static,
impl<Value> QueryKindTrait<Value, GetDefault> for OptionQuerywhere Value: FullCodec + 'static,
source§const METADATA: StorageEntryModifierIR = StorageEntryModifierIR::Optional
const METADATA: StorageEntryModifierIR = StorageEntryModifierIR::Optional
Metadata for the storage kind.
source§fn from_optional_value_to_query(v: Option<Value>) -> Self::Query
fn from_optional_value_to_query(v: Option<Value>) -> Self::Query
Convert an optional value (i.e. some if trie contains the value or none otherwise) to the
query.
source§fn from_query_to_optional_value(v: Self::Query) -> Option<Value>
fn from_query_to_optional_value(v: Self::Query) -> Option<Value>
Convert a query to an optional value.
Auto Trait Implementations§
impl RefUnwindSafe for OptionQuery
impl Send for OptionQuery
impl Sync for OptionQuery
impl Unpin for OptionQuery
impl UnwindSafe for OptionQuery
Blanket Implementations§
source§impl<T> BorrowMut<T> for Twhere
T: ?Sized,
impl<T> BorrowMut<T> for Twhere T: ?Sized,
source§fn borrow_mut(&mut self) -> &mut T
fn borrow_mut(&mut self) -> &mut T
Mutably borrows from an owned value. Read more
source§impl<T> CheckedConversion for T
impl<T> CheckedConversion for T
source§impl<T> FmtForward for T
impl<T> FmtForward for T
source§fn fmt_binary(self) -> FmtBinary<Self>where
Self: Binary,
fn fmt_binary(self) -> FmtBinary<Self>where Self: Binary,
Causes
self
to use its Binary
implementation when Debug
-formatted.source§fn fmt_display(self) -> FmtDisplay<Self>where
Self: Display,
fn fmt_display(self) -> FmtDisplay<Self>where Self: Display,
Causes
self
to use its Display
implementation when
Debug
-formatted.source§fn fmt_lower_exp(self) -> FmtLowerExp<Self>where
Self: LowerExp,
fn fmt_lower_exp(self) -> FmtLowerExp<Self>where Self: LowerExp,
Causes
self
to use its LowerExp
implementation when
Debug
-formatted.source§fn fmt_lower_hex(self) -> FmtLowerHex<Self>where
Self: LowerHex,
fn fmt_lower_hex(self) -> FmtLowerHex<Self>where Self: LowerHex,
Causes
self
to use its LowerHex
implementation when
Debug
-formatted.source§fn fmt_octal(self) -> FmtOctal<Self>where
Self: Octal,
fn fmt_octal(self) -> FmtOctal<Self>where Self: Octal,
Causes
self
to use its Octal
implementation when Debug
-formatted.source§fn fmt_pointer(self) -> FmtPointer<Self>where
Self: Pointer,
fn fmt_pointer(self) -> FmtPointer<Self>where Self: Pointer,
Causes
self
to use its Pointer
implementation when
Debug
-formatted.source§fn fmt_upper_exp(self) -> FmtUpperExp<Self>where
Self: UpperExp,
fn fmt_upper_exp(self) -> FmtUpperExp<Self>where Self: UpperExp,
Causes
self
to use its UpperExp
implementation when
Debug
-formatted.source§fn fmt_upper_hex(self) -> FmtUpperHex<Self>where
Self: UpperHex,
fn fmt_upper_hex(self) -> FmtUpperHex<Self>where Self: UpperHex,
Causes
self
to use its UpperHex
implementation when
Debug
-formatted.source§impl<T> Instrument for T
impl<T> Instrument for T
source§fn instrument(self, span: Span) -> Instrumented<Self>
fn instrument(self, span: Span) -> Instrumented<Self>
source§fn in_current_span(self) -> Instrumented<Self>
fn in_current_span(self) -> Instrumented<Self>
source§impl<T, Outer> IsWrappedBy<Outer> for Twhere
Outer: AsRef<T> + AsMut<T> + From<T>,
T: From<Outer>,
impl<T, Outer> IsWrappedBy<Outer> for Twhere Outer: AsRef<T> + AsMut<T> + From<T>, T: From<Outer>,
source§impl<T> Pipe for Twhere
T: ?Sized,
impl<T> Pipe for Twhere T: ?Sized,
source§fn pipe<R>(self, func: impl FnOnce(Self) -> R) -> Rwhere
Self: Sized,
fn pipe<R>(self, func: impl FnOnce(Self) -> R) -> Rwhere Self: Sized,
Pipes by value. This is generally the method you want to use. Read more
source§fn pipe_ref<'a, R>(&'a self, func: impl FnOnce(&'a Self) -> R) -> Rwhere
R: 'a,
fn pipe_ref<'a, R>(&'a self, func: impl FnOnce(&'a Self) -> R) -> Rwhere R: 'a,
Borrows
self
and passes that borrow into the pipe function. Read moresource§fn pipe_ref_mut<'a, R>(&'a mut self, func: impl FnOnce(&'a mut Self) -> R) -> Rwhere
R: 'a,
fn pipe_ref_mut<'a, R>(&'a mut self, func: impl FnOnce(&'a mut Self) -> R) -> Rwhere R: 'a,
Mutably borrows
self
and passes that borrow into the pipe function. Read moresource§fn pipe_borrow<'a, B, R>(&'a self, func: impl FnOnce(&'a B) -> R) -> Rwhere
Self: Borrow<B>,
B: 'a + ?Sized,
R: 'a,
fn pipe_borrow<'a, B, R>(&'a self, func: impl FnOnce(&'a B) -> R) -> Rwhere Self: Borrow<B>, B: 'a + ?Sized, R: 'a,
source§fn pipe_borrow_mut<'a, B, R>(
&'a mut self,
func: impl FnOnce(&'a mut B) -> R
) -> Rwhere
Self: BorrowMut<B>,
B: 'a + ?Sized,
R: 'a,
fn pipe_borrow_mut<'a, B, R>( &'a mut self, func: impl FnOnce(&'a mut B) -> R ) -> Rwhere Self: BorrowMut<B>, B: 'a + ?Sized, R: 'a,
source§fn pipe_as_ref<'a, U, R>(&'a self, func: impl FnOnce(&'a U) -> R) -> Rwhere
Self: AsRef<U>,
U: 'a + ?Sized,
R: 'a,
fn pipe_as_ref<'a, U, R>(&'a self, func: impl FnOnce(&'a U) -> R) -> Rwhere Self: AsRef<U>, U: 'a + ?Sized, R: 'a,
Borrows
self
, then passes self.as_ref()
into the pipe function.source§fn pipe_as_mut<'a, U, R>(&'a mut self, func: impl FnOnce(&'a mut U) -> R) -> Rwhere
Self: AsMut<U>,
U: 'a + ?Sized,
R: 'a,
fn pipe_as_mut<'a, U, R>(&'a mut self, func: impl FnOnce(&'a mut U) -> R) -> Rwhere Self: AsMut<U>, U: 'a + ?Sized, R: 'a,
Mutably borrows
self
, then passes self.as_mut()
into the pipe
function.source§impl<T> Pointable for T
impl<T> Pointable for T
source§impl<T> SaturatedConversion for T
impl<T> SaturatedConversion for T
source§fn saturated_from<T>(t: T) -> Selfwhere
Self: UniqueSaturatedFrom<T>,
fn saturated_from<T>(t: T) -> Selfwhere Self: UniqueSaturatedFrom<T>,
source§fn saturated_into<T>(self) -> Twhere
Self: UniqueSaturatedInto<T>,
fn saturated_into<T>(self) -> Twhere Self: UniqueSaturatedInto<T>,
Consume self to return an equivalent value of
T
. Read moresource§impl<T> Tap for T
impl<T> Tap for T
source§fn tap_borrow<B>(self, func: impl FnOnce(&B)) -> Selfwhere
Self: Borrow<B>,
B: ?Sized,
fn tap_borrow<B>(self, func: impl FnOnce(&B)) -> Selfwhere Self: Borrow<B>, B: ?Sized,
Immutable access to the
Borrow<B>
of a value. Read moresource§fn tap_borrow_mut<B>(self, func: impl FnOnce(&mut B)) -> Selfwhere
Self: BorrowMut<B>,
B: ?Sized,
fn tap_borrow_mut<B>(self, func: impl FnOnce(&mut B)) -> Selfwhere Self: BorrowMut<B>, B: ?Sized,
Mutable access to the
BorrowMut<B>
of a value. Read moresource§fn tap_ref<R>(self, func: impl FnOnce(&R)) -> Selfwhere
Self: AsRef<R>,
R: ?Sized,
fn tap_ref<R>(self, func: impl FnOnce(&R)) -> Selfwhere Self: AsRef<R>, R: ?Sized,
Immutable access to the
AsRef<R>
view of a value. Read moresource§fn tap_ref_mut<R>(self, func: impl FnOnce(&mut R)) -> Selfwhere
Self: AsMut<R>,
R: ?Sized,
fn tap_ref_mut<R>(self, func: impl FnOnce(&mut R)) -> Selfwhere Self: AsMut<R>, R: ?Sized,
Mutable access to the
AsMut<R>
view of a value. Read moresource§fn tap_deref<T>(self, func: impl FnOnce(&T)) -> Selfwhere
Self: Deref<Target = T>,
T: ?Sized,
fn tap_deref<T>(self, func: impl FnOnce(&T)) -> Selfwhere Self: Deref<Target = T>, T: ?Sized,
Immutable access to the
Deref::Target
of a value. Read moresource§fn tap_deref_mut<T>(self, func: impl FnOnce(&mut T)) -> Selfwhere
Self: DerefMut<Target = T> + Deref,
T: ?Sized,
fn tap_deref_mut<T>(self, func: impl FnOnce(&mut T)) -> Selfwhere Self: DerefMut<Target = T> + Deref, T: ?Sized,
Mutable access to the
Deref::Target
of a value. Read moresource§fn tap_dbg(self, func: impl FnOnce(&Self)) -> Self
fn tap_dbg(self, func: impl FnOnce(&Self)) -> Self
Calls
.tap()
only in debug builds, and is erased in release builds.source§fn tap_mut_dbg(self, func: impl FnOnce(&mut Self)) -> Self
fn tap_mut_dbg(self, func: impl FnOnce(&mut Self)) -> Self
Calls
.tap_mut()
only in debug builds, and is erased in release
builds.source§fn tap_borrow_dbg<B>(self, func: impl FnOnce(&B)) -> Selfwhere
Self: Borrow<B>,
B: ?Sized,
fn tap_borrow_dbg<B>(self, func: impl FnOnce(&B)) -> Selfwhere Self: Borrow<B>, B: ?Sized,
Calls
.tap_borrow()
only in debug builds, and is erased in release
builds.source§fn tap_borrow_mut_dbg<B>(self, func: impl FnOnce(&mut B)) -> Selfwhere
Self: BorrowMut<B>,
B: ?Sized,
fn tap_borrow_mut_dbg<B>(self, func: impl FnOnce(&mut B)) -> Selfwhere Self: BorrowMut<B>, B: ?Sized,
Calls
.tap_borrow_mut()
only in debug builds, and is erased in release
builds.source§fn tap_ref_dbg<R>(self, func: impl FnOnce(&R)) -> Selfwhere
Self: AsRef<R>,
R: ?Sized,
fn tap_ref_dbg<R>(self, func: impl FnOnce(&R)) -> Selfwhere Self: AsRef<R>, R: ?Sized,
Calls
.tap_ref()
only in debug builds, and is erased in release
builds.source§fn tap_ref_mut_dbg<R>(self, func: impl FnOnce(&mut R)) -> Selfwhere
Self: AsMut<R>,
R: ?Sized,
fn tap_ref_mut_dbg<R>(self, func: impl FnOnce(&mut R)) -> Selfwhere Self: AsMut<R>, R: ?Sized,
Calls
.tap_ref_mut()
only in debug builds, and is erased in release
builds.source§impl<S, T> UncheckedInto<T> for Swhere
T: UncheckedFrom<S>,
impl<S, T> UncheckedInto<T> for Swhere T: UncheckedFrom<S>,
source§fn unchecked_into(self) -> T
fn unchecked_into(self) -> T
The counterpart to
unchecked_from
.source§impl<T, S> UniqueSaturatedInto<T> for Swhere
T: Bounded,
S: TryInto<T>,
impl<T, S> UniqueSaturatedInto<T> for Swhere T: Bounded, S: TryInto<T>,
source§fn unique_saturated_into(self) -> T
fn unique_saturated_into(self) -> T
Consume self to return an equivalent value of
T
.