Struct JoinQuery 

pub struct JoinQuery {
    pub head: Predicate,
    pub body: Vec<Predicate>,
}

A parsed Datalog join query of the form Head :- Body1, Body2, ... .

For example: path(X, Z) :- edge(X, Y), edge(Y, Z).

Implements FromStr for parsing from a string.

Fields

head: Predicate

The head predicate defining the output schema.

body: Vec<Predicate>

The body predicates to be joined.

Trait Implementations

impl Clone for JoinQuery

fn clone(&self) -> JoinQuery

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for JoinQuery

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

Formats the value using the given formatter.

impl FromStr for JoinQuery

fn from_str(s: &str) -> Result<JoinQuery, <JoinQuery as FromStr>::Err>

Parses a Datalog rule into a JoinQuery.

Errors

Returns an error if s is not a single well-formed rule of the shape Head(…) :- Body1(…), …, BodyN(…). — including missing :-, empty body, missing terminating ., trailing content after the ., or identifiers that don’t match the syntax rules.

type Err = ErrMode<ContextError>

The associated error which can be returned from parsing.

impl PartialEq for JoinQuery

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for JoinQuery

impl StructuralPartialEq for JoinQuery