Struct datafrog::PrefixFilter

pub struct PrefixFilter<Tuple, Func: Fn(&Tuple) -> bool> { /* fields omitted */ }

A treefrog leaper that tests each of the tuples from the main input (the “prefix”). Use like PrefixFilter::from(|tuple| ...); if the closure returns true, then the tuple is retained, else it will be ignored. This leaper can be used in isolation in which case it just acts like a filter on the input (the “proposed value” will be () type).

Implementations

impl<'leap, Tuple, Func> PrefixFilter<Tuple, Func> where
    Func: Fn(&Tuple) -> bool, 

pub fn from(predicate: Func) -> Self

Creates a new filter based on the prefix

Trait Implementations

impl<'leap, Tuple, Val, Func> Leaper<'leap, Tuple, Val> for PrefixFilter<Tuple, Func> where
    Func: Fn(&Tuple) -> bool, 

fn count(&mut self, prefix: &Tuple) -> usize

Estimates the number of proposed values.

fn propose(&mut self, _prefix: &Tuple, _values: &mut Vec<&'leap Val>)

Populates values with proposed values.

fn intersect(&mut self, _prefix: &Tuple, _values: &mut Vec<&'leap Val>)

Restricts values to proposed values.

impl<'leap, Tuple, Func> Leapers<'leap, Tuple, ()> for PrefixFilter<Tuple, Func> where
    Func: Fn(&Tuple) -> bool, 

fn for_each_count(&mut self, tuple: &Tuple, op: impl FnMut(usize, usize))

Internal method:

fn propose(&mut self, _: &Tuple, min_index: usize, values: &mut Vec<&'leap ()>)

Internal method:

fn intersect(
    &mut self,
    _: &Tuple,
    min_index: usize,
    values: &mut Vec<&'leap ()>
)

Internal method: