Trait sgx_tstd::default::Default

pub trait Default {
    fn default() -> Self;
}

A trait for giving a type a useful default value.

Sometimes, you want to fall back to some kind of default value, and don't particularly care what it is. This comes up often with structs that define a set of options:

struct SomeOptions {
    foo: i32,
    bar: f32,
}

How can we define some default values? You can use Default:

#[derive(Default)]
struct SomeOptions {
    foo: i32,
    bar: f32,
}

fn main() {
    let options: SomeOptions = Default::default();
}

Now, you get all of the default values. Rust implements Default for various primitives types.

If you want to override a particular option, but still retain the other defaults:

fn main() {
    let options = SomeOptions { foo: 42, ..Default::default() };
}

Derivable

This trait can be used with #[derive] if all of the type's fields implement Default. When derived, it will use the default value for each field's type.

How can I implement Default?

Provide an implementation for the default() method that returns the value of your type that should be the default:

enum Kind {
    A,
    B,
    C,
}

impl Default for Kind {
    fn default() -> Kind { Kind::A }
}

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 }
}

Implementations on Foreign Types

impl Default for Duration

fn default() -> Duration

impl Default for Global

fn default() -> Global

impl Default for sgx_ps_cap_t

fn default() -> sgx_ps_cap_t

impl Default for sgx_cpu_context_t

fn default() -> sgx_cpu_context_t

impl Default for sgx_ra_msg3_t

fn default() -> sgx_ra_msg3_t

impl Default for sgx_mc_uuid_t

fn default() -> sgx_mc_uuid_t

impl Default for ecc_param_t

fn default() -> ecc_param_t

impl Default for sgx_dh_session_role_t

fn default() -> sgx_dh_session_role_t

impl Default for sgx_report_data_t

fn default() -> sgx_report_data_t

impl Default for sgx_ec256_public_t

fn default() -> sgx_ec256_public_t

impl Default for sgx_spid_t

fn default() -> sgx_spid_t

impl Default for sgx_uswitchless_worker_event_t

fn default() -> sgx_uswitchless_worker_event_t

impl Default for sgx_quote_t

fn default() -> sgx_quote_t

impl Default for sgx_dh_msg1_t

fn default() -> sgx_dh_msg1_t

impl Default for sgx_uswitchless_worker_type_t

fn default() -> sgx_uswitchless_worker_type_t

impl Default for sgx_dh_msg3_t

fn default() -> sgx_dh_msg3_t

impl Default for sgx_report_t

fn default() -> sgx_report_t

impl Default for sgx_misc_attribute_t

fn default() -> sgx_misc_attribute_t

impl Default for sgx_basename_t

fn default() -> sgx_basename_t

impl Default for sgx_dh_session_t

fn default() -> sgx_dh_session_t

impl Default for sgx_thread_mutexattr_t

fn default() -> sgx_thread_mutexattr_t

impl Default for sgx_dh_session_enclave_identity_t

fn default() -> sgx_dh_session_enclave_identity_t

impl Default for sgx_thread_condattr_t

fn default() -> sgx_thread_condattr_t

impl Default for sgx_measurement_t

fn default() -> sgx_measurement_t

impl Default for sgx_exception_info_t

fn default() -> sgx_exception_info_t

impl Default for sgx_rsa_result_t

fn default() -> sgx_rsa_result_t

impl Default for sgx_update_info_bit_t

fn default() -> sgx_update_info_bit_t

impl Default for sgx_generic_ecresult_t

fn default() -> sgx_generic_ecresult_t

impl Default for sgx_status_t

fn default() -> sgx_status_t

impl Default for sgx_uswitchless_worker_stats_t

fn default() -> sgx_uswitchless_worker_stats_t

impl Default for sgx_ps_sec_prop_desc_t

fn default() -> sgx_ps_sec_prop_desc_t

impl Default for sgx_rsa3072_signature_t

fn default() -> sgx_rsa3072_signature_t

impl Default for rsa_params_t

fn default() -> rsa_params_t

impl Default for sgx_key_request_t

fn default() -> sgx_key_request_t

impl Default for sgx_dh_msg2_t

fn default() -> sgx_dh_msg2_t

impl Default for sgx_dh_msg3_body_t

fn default() -> sgx_dh_msg3_body_t

impl Default for sgx_target_info_t

fn default() -> sgx_target_info_t

impl Default for sgx_ec256_signature_t

fn default() -> sgx_ec256_signature_t

impl Default for sgx_rsa_key_type_t

fn default() -> sgx_rsa_key_type_t

impl Default for sgx_report_body_t

fn default() -> sgx_report_body_t

impl Default for sgx_ec256_dh_shared_t

fn default() -> sgx_ec256_dh_shared_t

impl Default for sgx_ra_msg1_t

fn default() -> sgx_ra_msg1_t

impl Default for sgx_ec256_private_t

fn default() -> sgx_ec256_private_t

impl Default for sgx_exception_type_t

fn default() -> sgx_exception_type_t

impl Default for sgx_ra_msg2_t

fn default() -> sgx_ra_msg2_t

impl Default for sgx_ps_sec_prop_desc_ex_t

fn default() -> sgx_ps_sec_prop_desc_ex_t

impl Default for sgx_platform_info_t

fn default() -> sgx_platform_info_t

impl Default for sgx_uswitchless_config_t

fn default() -> sgx_uswitchless_config_t

impl Default for sgx_ra_key_type_t

fn default() -> sgx_ra_key_type_t

impl Default for sgx_key_id_t

fn default() -> sgx_key_id_t

impl Default for sgx_quote_nonce_t

fn default() -> sgx_quote_nonce_t

impl Default for sgx_cpu_svn_t

fn default() -> sgx_cpu_svn_t

impl Default for sgx_rsa3072_key_t

fn default() -> sgx_rsa3072_key_t

impl Default for sgx_rsa3072_public_key_t

fn default() -> sgx_rsa3072_public_key_t

impl Default for sgx_device_status_t

fn default() -> sgx_device_status_t

impl Default for sgx_sealed_data_t

fn default() -> sgx_sealed_data_t

impl Default for sgx_exception_vector_t

fn default() -> sgx_exception_vector_t

impl Default for sgx_attributes_t

fn default() -> sgx_attributes_t

impl Default for sgx_aes_gcm_data_t

fn default() -> sgx_aes_gcm_data_t

impl Default for sgx_quote_sign_type_t

fn default() -> sgx_quote_sign_type_t

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     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,     G: Default,     H: Default,     I: Default,     J: Default,     K: Default,     L: Default,

• impl<T> Default for [T; 23] where     T: Default,

• impl<T> Default for [T; 3] where     T: Default,

• impl Default for SipHasher

• impl Default for f32

• impl<H> Default for BuildHasherDefault<H>

• impl Default for i8

• impl<T> Default for Option<T>

• impl<T> Default for [T; 28] where     T: Default,

• impl<T> Default for [T; 26] where     T: Default,

• impl<T> Default for [T; 8] where     T: Default,

• impl<T> Default for [T; 10] where     T: Default,

• impl<T> Default for UnsafeCell<T> where     T: Default,

• impl<T> Default for [T; 1] where     T: Default,

• impl<T> Default for Empty<T>

• impl Default for i32

• impl Default for AtomicI8

• impl<A, B, C, D> Default for (A, B, C, D) where     A: Default,     B: Default,     C: Default,     D: Default,

• impl<A, B> Default for (A, B) where     A: Default,     B: Default,

• impl Default for i128

• impl<T> Default for Wrapping<T> where     T: Default,

• impl<T> Default for [T; 21] where     T: Default,

• impl<T> Default for [T; 2] where     T: Default,

• impl<T> Default for ManuallyDrop<T> where     T: Default,

• impl<T> Default for [T; 24] where     T: Default,

• impl<A, B, C, D, E> Default for (A, B, C, D, E) where     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,

• impl Default for usize

• impl Default for u16

• impl Default for AtomicBool

• impl<T> Default for [T; 25] where     T: Default,

• impl<T> Default for [T; 6] where     T: Default,

• impl Default for char

• impl Default for ()

• impl Default for Error

• impl<T> Default for [T; 17] where     T: Default,

• impl Default for u128

• impl Default for AtomicU16

• impl<'a, T> Default for &'a [T]

• impl<T> Default for AtomicPtr<T>

• impl<A, B, C, D, E, F> Default for (A, B, C, D, E, F) where     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,

• impl Default for AtomicI32

• impl<T> Default for [T; 4] where     T: Default,

• impl<T> Default for [T; 14] where     T: Default,

• impl<T> Default for [T; 11] where     T: Default,

• impl<A, B, C, D, E, F, G, H> Default for (A, B, C, D, E, F, G, H) where     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,     G: Default,     H: Default,

• impl<T> Default for [T; 13] where     T: Default,

• impl Default for u8

• impl Default for AtomicI64

• impl<A, B, C, D, E, F, G, H, I, J> Default for (A, B, C, D, E, F, G, H, I, J) where     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,     G: Default,     H: Default,     I: Default,     J: Default,

• impl<'a> Default for &'a mut str

• impl<T> Default for [T; 31] where     T: Default,

• impl<T> Default for [T; 30] where     T: Default,

• impl Default for u32

• impl<T> Default for Reverse<T> where     T: Default,

• impl<T> Default for [T; 29] where     T: Default,

• impl<T> Default for [T; 18] where     T: Default,

• impl<'a> Default for &'a str

• impl Default for AtomicU32

• impl Default for isize

• impl<T> Default for [T; 15] where     T: Default,

• impl<T> Default for [T; 32] where     T: Default,

• impl<T> Default for PhantomData<T> where     T: ?Sized,

• impl<'a, T> Default for &'a mut [T]

• impl Default for f64

• impl<A, B, C, D, E, F, G> Default for (A, B, C, D, E, F, G) where     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,     G: Default,

• impl Default for bool

• impl<T> Default for [T; 5] where     T: Default,

• impl Default for AtomicU64

• impl<T> Default for [T; 7] where     T: Default,

• impl Default for u64

• impl<T> Default for [T; 16] where     T: Default,

• impl<T> Default for [T; 22] where     T: Default,

• impl Default for AtomicUsize

• impl Default for i64

• impl<T> Default for RefCell<T> where     T: Default,

• impl<T> Default for [T; 0]

• impl<T> Default for [T; 20] where     T: Default,

• impl Default for AtomicIsize

• impl<A> Default for (A,) where     A: Default,

• impl<T> Default for [T; 9] where     T: Default,

• impl<T> Default for [T; 12] where     T: Default,

• impl<T> Default for Cell<T> where     T: Default,

• impl<T> Default for [T; 19] where     T: Default,

• impl<T> Default for [T; 27] where     T: Default,

• impl Default for AtomicI16

• impl Default for AtomicU8

• impl<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     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,     G: Default,     H: Default,     I: Default,     J: Default,     K: Default,

• impl<A, B, C> Default for (A, B, C) where     A: Default,     B: Default,     C: Default,

• impl Default for i16

• impl<A, B, C, D, E, F, G, H, I> Default for (A, B, C, D, E, F, G, H, I) where     A: Default,     B: Default,     C: Default,     D: Default,     E: Default,     F: Default,     G: Default,     H: Default,     I: Default,

• impl<T> Default for Rc<T> where     T: Default,

• impl Default for String

• impl<T> Default for sgx_tstd::rc::Weak<T>

• impl<T> Default for Box<[T]>

• impl<T> Default for BinaryHeap<T> where     T: Ord,

• impl<T> Default for sgx_tstd::sync::Weak<T>

• impl<T> Default for LinkedList<T>

• impl<K, V> Default for BTreeMap<K, V> where     K: Ord,

• impl<'a, B> Default for Cow<'a, B> where     B: ToOwned + ?Sized,     <B as ToOwned>::Owned: Default,

• impl<T> Default for Arc<T> where     T: Default,

• impl<T> Default for BTreeSet<T> where     T: Ord,

• impl Default for Box<str>

• impl<T> Default for VecDeque<T>

• impl<T> Default for Vec<T>

• impl<T> Default for Box<T> where     T: Default,

• impl<'a> Default for &'a CStr

• impl Default for Box<CStr>

• impl Default for CString

• impl<K, V, S> Default for HashMap<K, V, S> where     K: Eq + Hash,     S: BuildHasher + Default,

• impl Default for DefaultHasher

• impl Default for RandomState

• impl<T, S> Default for HashSet<T, S> where     T: Eq + Hash,     S: BuildHasher + Default,

• impl Default for OsString

• impl Default for Box<OsStr>

• impl<'a> Default for &'a OsStr

• impl Default for PathBuf

• impl Default for SgxCondvar

• impl<T: ?Sized + Default> Default for SgxMutex<T>

• impl<T: Default> Default for SgxRwLock<T>

• impl Default for SgxSpinlock

• impl Default for sgx_tstd::time::Duration