drop - Cryo

import std::core::drop; — in the prelude · source

`Drop`

type trait Drop {
    drop(mut &this) -> void;
}

Drop is the destructor: drop(mut &this) -> void, the last operation performed on a value. The compiler synthesises the call at scope exit - including the early exits ? and return take - and a manual .drop() remains available for early release. See Ownership, Copy, and Drop for when the call is inserted and what a move does to it.

Every primitive gets a trivial no-op impl so generic containers can write where K: Drop, V: Drop without locking out useful instantiations like HashMap<u32, V>; when the value carries no resource, the call lowers to no IR at all. The unit type () has one for the same reason - HashSet<T> is a HashMap<T, ()>.

The module is in the prelude because an implement trait Drop for X head has to resolve the trait name in every file that owns a resource, and the compiler reasons about Drop by identity rather than by spelling.

Implementors

Every owning type in the library. The primitive impls are the no-ops described above; the 128-bit and pointer-width integers have no explicit impl and need none.

implement trait Drop for i8

implement trait Drop for i16

implement trait Drop for i32

implement trait Drop for i64

implement trait Drop for u8

implement trait Drop for u16

implement trait Drop for u32

implement trait Drop for u64

implement trait Drop for f32

implement trait Drop for f64

implement trait Drop for boolean

implement trait Drop for char

implement trait Drop for string

implement trait Drop for ()

implement<T, A> trait Drop for struct Arc<T, A>
where T: Drop, A: Allocator   // std::alloc::arc

implement<T, A> trait Drop for struct Weak<T, A>
where T: Drop, A: Allocator   // std::alloc::arc

implement trait Drop for struct Arena   // std::alloc::arena_alloc

implement<T, A> trait Drop for struct Box<T, A>
where T: Drop, A: Allocator   // std::alloc::box

implement trait Drop for struct Pool   // std::alloc::pool

implement<T, A> trait Drop for struct Rc<T, A>
where T: Drop, A: Allocator   // std::alloc::rc

implement<T, A> trait Drop for struct Weak<T, A>
where T: Drop, A: Allocator   // std::alloc::rc

implement<T, A> trait Drop for struct Array<T, A>
where T: Drop, A: Allocator   // std::collections::array

implement<K, V, A> trait Drop for struct HashMap<K, V, A>
where K: Drop, V: Drop, A: Allocator   // std::collections::hashmap

implement<T, A> trait Drop for struct HashSet<T, A>
where T: Drop, A: Allocator   // std::collections::hashset

implement<A, B> trait Drop for struct Pair<A, B>
where A: Drop, B: Drop   // std::collections::pair

implement<T, A> trait Drop for struct RawBuffer<T, A>
where A: Allocator   // std::collections::raw_buffer

implement<A> trait Drop for struct String<A>
where A: Allocator   // std::collections::string

implement trait Drop for VaArgs   // std::core::varargs

implement trait Drop for struct DirEntry   // std::fs::dir

implement trait Drop for struct ReadDir   // std::fs::dir

implement trait Drop for struct File   // std::fs::file

implement<A> trait Drop for struct PathBuf<A>
where A: Allocator   // std::fs::path

implement trait Drop for struct Task   // std::future::executor

implement<O> trait Drop for struct JoinHandle<O>   // std::future::executor

implement trait Drop for struct Executor   // std::future::executor

implement trait Drop for struct Sleep   // std::future::timer

implement trait Drop for struct Waker   // std::future::waker

implement<W> trait Drop for struct BufWriter<W>   // std::io::buf

implement<W> trait Drop for struct LineWriter<W>   // std::io::buf

implement<R> trait Drop for struct BufReader<R>   // std::io::buf

implement trait Drop for struct BufStream<S>   // std::io::buf

implement trait Drop for struct Cursor   // std::io::cursor

implement trait Drop for struct StdinLock   // std::io::stdio

implement trait Drop for struct StdoutLock   // std::io::stdio

implement trait Drop for struct StderrLock   // std::io::stdio

implement trait Drop for struct JsonError   // std::json::error

implement trait Drop for struct JsonObject   // std::json::value

implement trait Drop for enum JsonValue   // std::json::value

implement trait Drop for struct Resolve   // std::net::dns

implement trait Drop for struct HeaderField   // std::net::http2::hpack

implement trait Drop for struct Headers   // std::net::http::headers

implement trait Drop for struct Request   // std::net::http::request

implement trait Drop for struct Response   // std::net::http::response

implement trait Drop for struct Route   // std::net::http::router

implement trait Drop for struct Router   // std::net::http::router

implement trait Drop for struct TcpRead   // std::net::socket::tcp

implement trait Drop for struct TcpWrite   // std::net::socket::tcp

implement trait Drop for struct TcpAccept   // std::net::socket::tcp

implement trait Drop for struct TcpConnect   // std::net::socket::tcp

implement trait Drop for struct UdpSendTo   // std::net::socket::udp

implement trait Drop for struct UdpSend   // std::net::socket::udp

implement trait Drop for struct UdpRecvFrom   // std::net::socket::udp

implement trait Drop for struct UdpRecv   // std::net::socket::udp

implement trait Drop for struct TlsHandshake   // std::net::tls::future

implement trait Drop for struct TlsRead   // std::net::tls::future

implement trait Drop for struct TlsWrite   // std::net::tls::future

implement trait Drop for struct WebSocket<S>   // std::net::ws::conn

implement trait Drop for struct ChildWait   // std::process::child

implement trait Drop for struct PipeDrain   // std::process::child

implement trait Drop for struct ChildStdin   // std::process::child

implement trait Drop for struct ChildStdout   // std::process::child

implement trait Drop for struct ChildStderr   // std::process::child

implement trait Drop for struct Child   // std::process::child

implement trait Drop for struct EnvEntry   // std::process::command

implement trait Drop for struct Command   // std::process::command

implement trait Drop for struct Output   // std::process::command

implement trait Drop for struct PipePair   // std::process::command

implement trait Drop for struct WeightedIndex   // std::random::distribution

implement trait Drop for struct Atomic<T>   // std::sync::atomic

implement trait Drop for struct Barrier   // std::sync::barrier

implement trait Drop for struct CondVar   // std::sync::condvar

implement<T> trait Drop for struct Sender<T>   // std::sync::mpsc

implement<T> trait Drop for struct Receiver<T>
where T: Drop   // std::sync::mpsc

implement<T, A> trait Drop for struct MutexGuard<T, A>   // std::sync::mutex

implement<T, A> trait Drop for struct Mutex<T, A>
where T: Drop, A: Allocator   // std::sync::mutex

implement trait Drop for struct Once   // std::sync::once

implement<T, A> trait Drop for struct RwLockReadGuard<T, A>   // std::sync::rwlock

implement<T, A> trait Drop for struct RwLockWriteGuard<T, A>   // std::sync::rwlock

implement<T, A> trait Drop for struct RwLock<T, A>
where T: Drop, A: Allocator   // std::sync::rwlock

implement trait Drop for enum TestError   // std::test::error

implement trait Drop for struct RunOptions   // std::test::runner

implement trait Drop for struct TestRun   // std::test::runner

implement trait Drop for struct ReporterState   // std::test::runner

implement trait Drop for struct WorkerResult   // std::test::runner

implement trait Drop for struct TestRunner   // std::test::runner

implement<T> trait Drop for struct JoinHandle<T>   // std::thread

implement trait Drop for struct Scope   // std::thread

implement<T> trait Drop for struct ThreadLocal<T>   // std::thread::local

Drop#

Implementors#

`Drop`

Implementors