summaryrefslogtreecommitdiff
path: root/library/std/src/prelude/mod.rs
diff options
context:
space:
mode:
Diffstat (limited to 'library/std/src/prelude/mod.rs')
-rw-r--r--library/std/src/prelude/mod.rs120
1 files changed, 120 insertions, 0 deletions
diff --git a/library/std/src/prelude/mod.rs b/library/std/src/prelude/mod.rs
new file mode 100644
index 00000000000..48f7cf16988
--- /dev/null
+++ b/library/std/src/prelude/mod.rs
@@ -0,0 +1,120 @@
+//! 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`]: ../io/prelude/index.html
+//!
+//! 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 current version of the prelude (version 1) lives in
+//! [`std::prelude::v1`], and re-exports the following.
+//!
+//! * [`std::marker`]::{[`Copy`], [`Send`], [`Sized`], [`Sync`], [`Unpin`]}. The
+//! marker traits 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`, `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`, `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`](../vec/struct.Vec.html), a growable, heap-allocated
+//! vector.
+//!
+//! [`AsMut`]: ../convert/trait.AsMut.html
+//! [`AsRef`]: ../convert/trait.AsRef.html
+//! [`Box`]: ../boxed/struct.Box.html
+//! [`Clone`]: ../clone/trait.Clone.html
+//! [`Copy`]: ../marker/trait.Copy.html
+//! [`Default`]: ../default/trait.Default.html
+//! [`DoubleEndedIterator`]: ../iter/trait.DoubleEndedIterator.html
+//! [`Drop`]: ../ops/trait.Drop.html
+//! [`Eq`]: ../cmp/trait.Eq.html
+//! [`ExactSizeIterator`]: ../iter/trait.ExactSizeIterator.html
+//! [`Extend`]: ../iter/trait.Extend.html
+//! [`FnMut`]: ../ops/trait.FnMut.html
+//! [`FnOnce`]: ../ops/trait.FnOnce.html
+//! [`Fn`]: ../ops/trait.Fn.html
+//! [`From`]: ../convert/trait.From.html
+//! [`IntoIterator`]: ../iter/trait.IntoIterator.html
+//! [`Into`]: ../convert/trait.Into.html
+//! [`Iterator`]: ../iter/trait.Iterator.html
+//! [`Option`]: ../option/enum.Option.html
+//! [`Ord`]: ../cmp/trait.Ord.html
+//! [`PartialEq`]: ../cmp/trait.PartialEq.html
+//! [`PartialOrd`]: ../cmp/trait.PartialOrd.html
+//! [`Result`]: ../result/enum.Result.html
+//! [`Send`]: ../marker/trait.Send.html
+//! [`Sized`]: ../marker/trait.Sized.html
+//! [`SliceConcatExt`]: ../slice/trait.SliceConcatExt.html
+//! [`String`]: ../string/struct.String.html
+//! [`Sync`]: ../marker/trait.Sync.html
+//! [`ToOwned`]: ../borrow/trait.ToOwned.html
+//! [`ToString`]: ../string/trait.ToString.html
+//! [`Unpin`]: ../marker/trait.Unpin.html
+//! [`Vec`]: ../vec/struct.Vec.html
+//! [`Clone::clone`]: ../clone/trait.Clone.html#tymethod.clone
+//! [`mem::drop`]: ../mem/fn.drop.html
+//! [`std::borrow`]: ../borrow/index.html
+//! [`std::boxed`]: ../boxed/index.html
+//! [`std::clone`]: ../clone/index.html
+//! [`std::cmp`]: ../cmp/index.html
+//! [`std::convert`]: ../convert/index.html
+//! [`std::default`]: ../default/index.html
+//! [`std::iter`]: ../iter/index.html
+//! [`std::marker`]: ../marker/index.html
+//! [`std::mem`]: ../mem/index.html
+//! [`std::ops`]: ../ops/index.html
+//! [`std::option`]: ../option/index.html
+//! [`std::prelude::v1`]: v1/index.html
+//! [`std::result`]: ../result/index.html
+//! [`std::slice`]: ../slice/index.html
+//! [`std::string`]: ../string/index.html
+//! [`std::vec`]: ../vec/index.html
+//! [`to_owned`]: ../borrow/trait.ToOwned.html#tymethod.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;