From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:02:58 +0200 Subject: Adding upstream version 1.64.0+dfsg1. Signed-off-by: Daniel Baumann --- library/std/src/prelude/mod.rs | 148 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 library/std/src/prelude/mod.rs (limited to 'library/std/src/prelude/mod.rs') diff --git a/library/std/src/prelude/mod.rs b/library/std/src/prelude/mod.rs new file mode 100644 index 000000000..c314bbbb6 --- /dev/null +++ b/library/std/src/prelude/mod.rs @@ -0,0 +1,148 @@ +//! # The Rust Prelude +//! +//! Rust comes with a variety of things in its standard library. However, if +//! you had to manually import every single thing that you used, it would be +//! very verbose. But importing a lot of things that a program never uses isn't +//! good either. A balance needs to be struck. +//! +//! The *prelude* is the list of things that Rust automatically imports into +//! every Rust program. It's kept as small as possible, and is focused on +//! things, particularly traits, which are used in almost every single Rust +//! program. +//! +//! # Other preludes +//! +//! Preludes can be seen as a pattern to make using multiple types more +//! convenient. As such, you'll find other preludes in the standard library, +//! such as [`std::io::prelude`]. Various libraries in the Rust ecosystem may +//! also define their own preludes. +//! +//! [`std::io::prelude`]: crate::io::prelude +//! +//! The difference between 'the prelude' and these other preludes is that they +//! are not automatically `use`'d, and must be imported manually. This is still +//! easier than importing all of their constituent components. +//! +//! # Prelude contents +//! +//! The first version of the prelude is used in Rust 2015 and Rust 2018, +//! and lives in [`std::prelude::v1`]. +//! [`std::prelude::rust_2015`] and [`std::prelude::rust_2018`] re-export this prelude. +//! It re-exports the following: +//! +//! * [std::marker]::{[Copy], [Send], [Sized], [Sync], [Unpin]}, +//! marker traits that indicate fundamental properties of types. +//! * [std::ops]::{[Drop], [Fn], [FnMut], [FnOnce]}, various +//! operations for both destructors and overloading `()`. +//! * [std::mem]::[drop][mem::drop], a convenience function for explicitly +//! dropping a value. +//! * [std::boxed]::[Box], a way to allocate values on the heap. +//! * [std::borrow]::[ToOwned], the conversion trait that defines +//! [`to_owned`], the generic method for creating an owned type from a +//! borrowed type. +//! * [std::clone]::[Clone], the ubiquitous trait that defines +//! [`clone`][Clone::clone], the method for producing a copy of a value. +//! * [std::cmp]::{[PartialEq], [PartialOrd], [Eq], [Ord]}, the +//! comparison traits, which implement the comparison operators and are often +//! seen in trait bounds. +//! * [std::convert]::{[AsRef], [AsMut], [Into], [From]}, generic +//! conversions, used by savvy API authors to create overloaded methods. +//! * [std::default]::[Default], types that have default values. +//! * [std::iter]::{[Iterator], [Extend], [IntoIterator], [DoubleEndedIterator], [ExactSizeIterator]}, +//! iterators of various +//! kinds. +//! * [std::option]::[Option]::{[self][Option], [Some], [None]}, a +//! type which expresses the presence or absence of a value. This type is so +//! commonly used, its variants are also exported. +//! * [std::result]::[Result]::{[self][Result], [Ok], [Err]}, a type +//! for functions that may succeed or fail. Like [`Option`], its variants are +//! exported as well. +//! * [std::string]::{[String], [ToString]}, heap-allocated strings. +//! * [std::vec]::[Vec], a growable, heap-allocated vector. +//! +//! The prelude used in Rust 2021, [`std::prelude::rust_2021`], includes all of the above, +//! and in addition re-exports: +//! +//! * [std::convert]::{[TryFrom], [TryInto]}, +//! * [std::iter]::[FromIterator]. +//! +//! [mem::drop]: crate::mem::drop +//! [std::borrow]: crate::borrow +//! [std::boxed]: crate::boxed +//! [std::clone]: crate::clone +//! [std::cmp]: crate::cmp +//! [std::convert]: crate::convert +//! [std::default]: crate::default +//! [std::iter]: crate::iter +//! [std::marker]: crate::marker +//! [std::mem]: crate::mem +//! [std::ops]: crate::ops +//! [std::option]: crate::option +//! [`std::prelude::v1`]: v1 +//! [`std::prelude::rust_2015`]: rust_2015 +//! [`std::prelude::rust_2018`]: rust_2018 +//! [`std::prelude::rust_2021`]: rust_2021 +//! [std::result]: crate::result +//! [std::slice]: crate::slice +//! [std::string]: crate::string +//! [std::vec]: mod@crate::vec +//! [TryFrom]: crate::convert::TryFrom +//! [TryInto]: crate::convert::TryInto +//! [FromIterator]: crate::iter::FromIterator +//! [`to_owned`]: crate::borrow::ToOwned::to_owned +//! [book-closures]: ../../book/ch13-01-closures.html +//! [book-dtor]: ../../book/ch15-03-drop.html +//! [book-enums]: ../../book/ch06-01-defining-an-enum.html +//! [book-iter]: ../../book/ch13-02-iterators.html + +#![stable(feature = "rust1", since = "1.0.0")] + +pub mod v1; + +/// The 2015 version of the prelude of The Rust Standard Library. +/// +/// See the [module-level documentation](self) for more. +#[stable(feature = "prelude_2015", since = "1.55.0")] +pub mod rust_2015 { + #[stable(feature = "prelude_2015", since = "1.55.0")] + #[doc(no_inline)] + pub use super::v1::*; +} + +/// The 2018 version of the prelude of The Rust Standard Library. +/// +/// See the [module-level documentation](self) for more. +#[stable(feature = "prelude_2018", since = "1.55.0")] +pub mod rust_2018 { + #[stable(feature = "prelude_2018", since = "1.55.0")] + #[doc(no_inline)] + pub use super::v1::*; +} + +/// The 2021 version of the prelude of The Rust Standard Library. +/// +/// See the [module-level documentation](self) for more. +#[stable(feature = "prelude_2021", since = "1.55.0")] +pub mod rust_2021 { + #[stable(feature = "prelude_2021", since = "1.55.0")] + #[doc(no_inline)] + pub use super::v1::*; + + #[stable(feature = "prelude_2021", since = "1.55.0")] + #[doc(no_inline)] + pub use core::prelude::rust_2021::*; +} + +/// The 2024 version of the prelude of The Rust Standard Library. +/// +/// See the [module-level documentation](self) for more. +#[unstable(feature = "prelude_2024", issue = "none")] +pub mod rust_2024 { + #[unstable(feature = "prelude_2024", issue = "none")] + #[doc(no_inline)] + pub use super::v1::*; + + #[unstable(feature = "prelude_2024", issue = "none")] + #[doc(no_inline)] + pub use core::prelude::rust_2024::*; +} -- cgit v1.2.3