Trait map_for::Filter

pub trait Filter<Item> {
    type Item;
    fn filter<P>(self, predicate: P) -> Option<Item>
    where
        P: FnOnce(&Self::Item) -> bool;
}

This trait creates a filter method for Option so that it can be filtered on when used in the map_for macro.

Example:

use map_for::{ Filter, FlatMap };
let c = map_for!{
   a <- Some (1);
   if (a%2) == 0;
   b <- Some (2);
   => { a + b } };
assert_eq!(c, None);

Associated Types

type Item

Required Methods

fn filter<P>(self, predicate: P) -> Option<Item> where
    P: FnOnce(&Self::Item) -> bool, 

Implementations on Foreign Types

impl<Item> Filter<Item> for Option<Item>

type Item = Item

fn filter<P>(self, predicate: P) -> Option<Item> where
    P: FnOnce(&Self::Item) -> bool, 

Implementors