pub enum Expression {
    Variable(Variable),
    Literal(Value),
}
Expand description

An un-evaluated Value.

Variants§

§

Variable(Variable)

Un-evaluated.

§

Literal(Value)

Evaluated.

Implementations§

source§

impl Expression

source

pub fn with_literal<S: Into<Scalar>>(literal: S) -> Self

Create an expression from a scalar literal.

source

pub fn into_literal(self) -> Option<Value>

Convert into a literal if possible.

source

pub fn into_variable(self) -> Option<Variable>

Convert into a variable, if possible.

source

pub fn try_evaluate<'c>( &'c self, runtime: &'c dyn Runtime ) -> Option<ValueCow<'c>>

Convert to a Value.

source

pub fn evaluate<'c>(&'c self, runtime: &'c dyn Runtime) -> Result<ValueCow<'c>>

Convert to a Value.

Trait Implementations§

source§

impl Clone for Expression

source§

fn clone(&self) -> Expression

Returns a copy of the value. Read more
1.0.0 · source§

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

Performs copy-assignment from source. Read more
source§

impl Debug for Expression

source§

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

Formats the value using the given formatter. Read more
source§

impl Display for Expression

source§

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

Formats the value using the given formatter. Read more
source§

impl Extend<Expression> for Variable

source§

fn extend<T: IntoIterator<Item = Expression>>(&mut self, iter: T)

Extends a collection with the contents of an iterator. Read more
source§

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)
Extends a collection with exactly one element.
source§

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
source§

impl PartialEq<Expression> for Expression

source§

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

This method tests for self and other values to be equal, and is used by ==.
1.0.0 · source§

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
source§

impl StructuralPartialEq for Expression

Auto Trait Implementations§

Blanket Implementations§

source§

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

source§

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
source§

impl<T> Borrow<T> for Twhere T: ?Sized,

source§

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
source§

impl<T> BorrowMut<T> for Twhere T: ?Sized,

source§

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

Mutably borrows from an owned value. Read more
source§

impl<T> From<T> for T

source§

fn from(t: T) -> T

Returns the argument unchanged.

source§

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

source§

fn into(self) -> U

Calls U::from(self).

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

source§

impl<T> ToOwned for Twhere T: Clone,

§

type Owned = T

The resulting type after obtaining ownership.
source§

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more
source§

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more
source§

impl<T> ToString for Twhere T: Display + ?Sized,

source§

default fn to_string(&self) -> String

Converts the given value to a String. Read more
source§

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

§

type Error = Infallible

The type returned in the event of a conversion error.
source§

fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
source§

impl<T, U> TryInto<U> for Twhere U: TryFrom<T>,

§

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

The type returned in the event of a conversion error.
source§

fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
source§

impl<T> Any for Twhere T: Any,

source§

impl<T> CloneAny for Twhere T: Any + Clone,

source§

impl<T> CloneAnySend for Twhere T: Any + Send + Clone,

source§

impl<T> CloneAnySendSync for Twhere T: Any + Send + Sync + Clone,

source§

impl<T> CloneAnySync for Twhere T: Any + Sync + Clone,