Struct mentat_ffi::RelResult

pub struct RelResult<T> {
    pub width: usize,
    pub values: Vec<T>,
}

The result you get from a 'rel' query, like:

[:find ?person ?name
 :where [?person :person/name ?name]]

There are three ways to get data out of a RelResult:

• By iterating over rows as slices. Use result.rows(). This is efficient and is recommended in two cases:
  1. If you don't need to take ownership of the resulting values (e.g., you're comparing or making a modified clone).
  2. When the data you're retrieving is cheap to clone. All scalar values are relatively cheap: they're either small values or Rc.
• By direct reference to a row by index, using result.row(i). This also returns a reference.
• By consuming the results using into_iter. This allocates short-lived vectors, but gives you ownership of the enclosed TypedValues.

Fields

width: usize

values: Vec<T>

Methods

impl<T> RelResult<T>

pub fn empty(width: usize) -> RelResult<T>

pub fn is_empty(&self) -> bool

pub fn row_count(&self) -> usize

Important traits for Chunks<'a, T>

impl<'a, T> Iterator for Chunks<'a, T> type Item = &'a [T];

pub fn rows(&self) -> Chunks<T>

pub fn row(&self, index: usize) -> Option<&[T]>

Trait Implementations

impl<T> IntoIterator for RelResult<T>

type Item = Vec<T>

The type of the elements being iterated over.

type IntoIter = SubvecIntoIterator<T>

Which kind of iterator are we turning this into?

fn into_iter(self) -> <RelResult<T> as IntoIterator>::IntoIter

Creates an iterator from a value.

impl<T> Clone for RelResult<T> where     T: Clone,

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

Returns a copy of the value.

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

Performs copy-assignment from source.

impl From<Vec<Vec<TypedValue>>> for RelResult<Binding>

fn from(src: Vec<Vec<TypedValue>>) -> RelResult<Binding>

Performs the conversion.

impl<T> Eq for RelResult<T> where     T: Eq,

impl<T> PartialEq<RelResult<T>> for RelResult<T> where     T: PartialEq<T>,

fn eq(&self, __arg_0: &RelResult<T>) -> bool

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

fn ne(&self, __arg_0: &RelResult<T>) -> bool

This method tests for !=.

impl<T> Debug for RelResult<T> where     T: Debug,

fn fmt(&self, __arg_0: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.