1b42e890bf
This commit modifies rustdoc to not require these empty modules to be public in the standard library. The modules still remain as a location to attach documentation to, but the modules themselves are now private (don't have to commit to an API). The documentation for the standard library now shows all of the primitive types on the main index page.
46 lines
1.3 KiB
Rust
46 lines
1.3 KiB
Rust
// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
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// file at the top-level directory of this distribution and at
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// http://rust-lang.org/COPYRIGHT.
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//
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// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
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// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
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// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
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// option. This file may not be copied, modified, or distributed
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// except according to those terms.
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#![doc(primitive = "unit")]
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#![stable]
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//! The `()` type, sometimes called "unit" or "nil".
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//!
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//! The `()` type has exactly one value `()`, and is used when there
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//! is no other meaningful value that could be returned. `()` is most
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//! commonly seen implicitly: functions without a `-> ...` implicitly
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//! have return type `()`, that is, these are equivalent:
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//!
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//! ```rust
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//! fn long() -> () {}
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//!
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//! fn short() {}
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//! ```
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//!
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//! The semicolon `;` can be used to discard the result of an
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//! expression at the end of a block, making the expression (and thus
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//! the block) evaluate to `()`. For example,
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//!
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//! ```rust
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//! fn returns_i64() -> i64 {
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//! 1i64
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//! }
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//! fn returns_unit() {
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//! 1i64;
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//! }
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//!
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//! let is_i64 = {
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//! returns_i64()
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//! };
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//! let is_unit = {
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//! returns_i64();
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//! };
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//! ```
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