Struct canrun::value::LVar

pub struct LVar<T: ?Sized> { /* fields omitted */ }

A logical variable that represents a potential value of type T.

They are typically created with the var() function.

LVars are are passed into goals to relate values and other variables to each other. They can also be used to query for values in a ResolvedState.

The identity of each LVar is tracked using an internal id. While this id is visible through the Debug implementation, it should only be used for debugging purposes as no guarantees are made about the type or generation of the id value.

Implementations

impl<T> LVar<T>

pub fn new() -> LVar<T>

Create a new logical var.

The var() function is typically used as a shorthand.

Example:

use canrun::{LVar};

let x: LVar<i32> = LVar::new();

pub fn labeled(label: &'static str) -> LVar<T>

Create a labeled logical var.

LVars are primarily represented by an internal id. A textual label can assist in debugging.

No guarantees are made about the actual debug string. Two LVars created separately are not considered to be the same, even if they have the same label.

Examples:

use canrun::{LVar};

let x: LVar<i32> = LVar::labeled("foo");
assert!(format!("{:?}", x).contains("foo"));

let x: LVar<i32> = LVar::labeled("foo");
let y: LVar<i32> = LVar::labeled("foo");
assert_eq!(x, x);
assert_ne!(x, y);

Trait Implementations

impl<T> Clone for LVar<T>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T> Copy for LVar<T>

impl<T> Debug for LVar<T>

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

Formats the value using the given formatter.

impl<T: Default + ?Sized> Default for LVar<T>

fn default() -> LVar<T>

Returns the "default value" for a type.

impl<T> Eq for LVar<T>

impl<T> Hash for LVar<T>

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, 

Feeds a slice of this type into the given [Hasher].

impl<T: Debug> IntoVal<T> for LVar<T>

fn into_val(self) -> Val<T>

Convert various T related values into a Val<T>.

impl<'_, T: Debug> IntoVal<T> for &'_ LVar<T>

fn into_val(self) -> Val<T>

Convert various T related values into a Val<T>.

impl<T> PartialEq<LVar<T>> for LVar<T>

fn eq(&self, other: &LVar<T>) -> bool

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

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl<'a, T, D> ReifyIn<'a, D> for LVar<T> where
    T: ReifyIn<'a, D> + Debug,
    D: DomainType<'a, T> + 'a, 

type Reified = T::Reified

The "concrete" type that Self reifies to.

fn reify_in(&self, state: &ResolvedState<D>) -> Option<Self::Reified>

Extract a reified Self from a compatible ResolvedState. This trait is usually used indirectly through the Query trait.