Struct codd::expression::Relation

pub struct Relation<T> where
    T: Tuple,  { /* fields omitted */ }

Is an expression corresponding to a relation with tuples of type T that is identified by a name.

Example:

use codd::{Database, expression::Relation};

let mut db = Database::new();
let r = db.add_relation("R").unwrap();

db.insert(&r, vec![0, 1, 2, 3].into()).unwrap(); // insert into the relation instance

assert_eq!(vec![0, 1, 2, 3], db.evaluate(&r).unwrap().into_tuples());

Implementations

impl<T> Relation<T> where
    T: Tuple, 

pub fn new<S>(name: S) -> Self where
    S: Into<String>, 

Creates a new Relation with a given name.

pub fn name(&self) -> &str

Returns a reference to the name by which the relation is identified.

Trait Implementations

impl<T: Clone> Clone for Relation<T> where
    T: Tuple, 

fn clone(&self) -> Relation<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for Relation<T> where
    T: Tuple, 

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

Formats the value using the given formatter.

impl<T> Expression<T> for Relation<T> where
    T: Tuple + 'static, 

fn visit<V>(&self, visitor: &mut V) where
    V: Visitor, 

Visits this expression by a Visitor.

fn builder(&self) -> Builder<T, Self>

Returns an expression builder over this expression.

impl<T: Tuple> From<Relation<T>> for Mono<T>

fn from(relation: Relation<T>) -> Self

Performs the conversion.