Trait bitflags::__core::default::Default
[−]
[src]
pub trait Default {
fn default() -> Self;
}A trait for giving a type a useful default value.
A struct can derive default implementations of Default for basic types using
#[derive(Default)].
Examples
#[derive(Default)] struct SomeOptions { foo: i32, bar: f32, }
Required Methods
fn default() -> Self
Returns the "default value" for a type.
Default values are often some kind of initial value, identity value, or anything else that may make sense as a default.
Examples
Using built-in default values:
let i: i8 = Default::default(); let (x, y): (Option<String>, f64) = Default::default(); let (a, b, (c, d)): (i32, u32, (bool, bool)) = Default::default();
Making your own:
enum Kind { A, B, C, } impl Default for Kind { fn default() -> Kind { Kind::A } }
Implementors
impl<A, B, C, D, E, F, G, H, I, J, K, L> Default for (A, B, C, D, E, F, G, H, I, J, K, L) where I: Default, E: Default, D: Default, H: Default, K: Default, C: Default, G: Default, A: Default, J: Default, B: Default, F: Default, L: Defaultimpl<A, B, C, D, E, F, G, H, I, J, K> Default for (A, B, C, D, E, F, G, H, I, J, K) where J: Default, C: Default, D: Default, B: Default, F: Default, I: Default, A: Default, H: Default, K: Default, G: Default, E: Defaultimpl<A, B, C, D, E, F, G, H, I, J> Default for (A, B, C, D, E, F, G, H, I, J) where H: Default, D: Default, E: Default, F: Default, A: Default, I: Default, J: Default, C: Default, B: Default, G: Defaultimpl<A, B, C, D, E, F, G, H, I> Default for (A, B, C, D, E, F, G, H, I) where C: Default, D: Default, I: Default, E: Default, A: Default, H: Default, G: Default, F: Default, B: Defaultimpl<A, B, C, D, E, F, G, H> Default for (A, B, C, D, E, F, G, H) where E: Default, G: Default, B: Default, H: Default, A: Default, F: Default, D: Default, C: Defaultimpl<A, B, C, D, E, F, G> Default for (A, B, C, D, E, F, G) where G: Default, C: Default, E: Default, A: Default, B: Default, F: Default, D: Defaultimpl<A, B, C, D, E, F> Default for (A, B, C, D, E, F) where F: Default, A: Default, C: Default, B: Default, E: Default, D: Defaultimpl<A, B, C, D, E> Default for (A, B, C, D, E) where A: Default, D: Default, B: Default, E: Default, C: Defaultimpl<A, B, C, D> Default for (A, B, C, D) where B: Default, C: Default, A: Default, D: Defaultimpl<A, B, C> Default for (A, B, C) where B: Default, A: Default, C: Defaultimpl<A, B> Default for (A, B) where A: Default, B: Defaultimpl<A> Default for (A,) where A: Defaultimpl<'a> Default for &'a strimpl<'a, T> Default for &'a mut [T]impl<'a, T> Default for &'a [T]impl<T> Default for [T; 0]impl<T> Default for [T; 1] where T: Defaultimpl<T> Default for [T; 2] where T: Defaultimpl<T> Default for [T; 3] where T: Defaultimpl<T> Default for [T; 4] where T: Defaultimpl<T> Default for [T; 5] where T: Defaultimpl<T> Default for [T; 6] where T: Defaultimpl<T> Default for [T; 7] where T: Defaultimpl<T> Default for [T; 8] where T: Defaultimpl<T> Default for [T; 9] where T: Defaultimpl<T> Default for [T; 10] where T: Defaultimpl<T> Default for [T; 11] where T: Defaultimpl<T> Default for [T; 12] where T: Defaultimpl<T> Default for [T; 13] where T: Defaultimpl<T> Default for [T; 14] where T: Defaultimpl<T> Default for [T; 15] where T: Defaultimpl<T> Default for [T; 16] where T: Defaultimpl<T> Default for [T; 17] where T: Defaultimpl<T> Default for [T; 18] where T: Defaultimpl<T> Default for [T; 19] where T: Defaultimpl<T> Default for [T; 20] where T: Defaultimpl<T> Default for [T; 21] where T: Defaultimpl<T> Default for [T; 22] where T: Defaultimpl<T> Default for [T; 23] where T: Defaultimpl<T> Default for [T; 24] where T: Defaultimpl<T> Default for [T; 25] where T: Defaultimpl<T> Default for [T; 26] where T: Defaultimpl<T> Default for [T; 27] where T: Defaultimpl<T> Default for [T; 28] where T: Defaultimpl<T> Default for [T; 29] where T: Defaultimpl<T> Default for [T; 30] where T: Defaultimpl<T> Default for [T; 31] where T: Defaultimpl<T> Default for [T; 32] where T: Defaultimpl Default for f64impl Default for f32impl Default for i64impl Default for i32impl Default for i16impl Default for i8impl Default for isizeimpl Default for u64impl Default for u32impl Default for u16impl Default for u8impl Default for usizeimpl Default for charimpl Default for boolimpl Default for ()impl<T> Default for Option<T>impl<T> Default for Box<[T]>impl<T> Default for Box<T> where T: Defaultimpl<T> Default for Vec<T>impl Default for Stringimpl<T> Default for Wrapping<T> where T: Defaultimpl<K, V, S> Default for HashMap<K, V, S> where K: Eq + Hash, S: BuildHasher + Defaultimpl Default for RandomStateimpl<T, S> Default for HashSet<T, S> where T: Eq + Hash, S: BuildHasher + Defaultimpl<T> Default for BinaryHeap<T> where T: Ordimpl<T> Default for VecDeque<T>impl<T> Default for LinkedList<T>impl<K, V> Default for BTreeMap<K, V> where K: Ordimpl<T> Default for BTreeSet<T> where T: Ordimpl<T> Default for Arc<T> where T: Defaultimpl Default for AtomicBoolimpl Default for AtomicIsizeimpl Default for AtomicUsizeimpl<T> Default for AtomicPtr<T>impl<T> Default for Rc<T> where T: Defaultimpl Default for Errorimpl<T> Default for PhantomData<T> where T: ?Sizedimpl<H> Default for BuildHasherDefault<H>impl Default for SipHasherimpl<T> Default for Empty<T>impl<T> Default for Cell<T> where T: Copy + Defaultimpl<T> Default for RefCell<T> where T: Defaultimpl<T> Default for UnsafeCell<T> where T: Default