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> CheckedConversion for T
impl<T> CheckedConversion for T
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>,
§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<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
.