Struct mentat_query_projector::ConstantProjector

pub struct ConstantProjector { /* fields omitted */ }

A projector that produces a QueryResult containing fixed data. Takes a boxed function that should return an empty result set of the desired type.

Methods

impl ConstantProjector

pub fn new(
    spec: Rc<FindSpec>,
    results_factory: Box<Fn() -> QueryResults>
) -> ConstantProjector

pub fn project_without_rows<'stmt>(&self) -> Result<QueryOutput>

Trait Implementations

impl Projector for ConstantProjector

fn project<'stmt, 's>(
    &self,
    _schema: &Schema,
    _sqlite: &'s Connection,
    _rows: Rows<'stmt>
) -> Result<QueryOutput>

fn columns<'s>(&'s self) -> Box<Iterator<Item = &Element> + 's>