Improve range docs

* Mention that `RangeFull` is a ZST and thus a singleton
* Improve code formatting and legibility
* Various other readability improvements
This commit is contained in:
Camelid 2020-10-12 14:53:41 -07:00
parent f3ab6f0584
commit a885c5008c
1 changed files with 52 additions and 40 deletions

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@ -19,7 +19,7 @@ use crate::hash::Hash;
///
/// ```compile_fail,E0277
/// for i in .. {
/// // ...
/// // ...
/// }
/// ```
///
@ -27,12 +27,12 @@ use crate::hash::Hash;
///
/// ```
/// let arr = [0, 1, 2, 3, 4];
/// assert_eq!(arr[ .. ], [0,1,2,3,4]); // RangeFull
/// assert_eq!(arr[ .. 3], [0,1,2 ]);
/// assert_eq!(arr[ ..=3], [0,1,2,3 ]);
/// assert_eq!(arr[1.. ], [ 1,2,3,4]);
/// assert_eq!(arr[1.. 3], [ 1,2 ]);
/// assert_eq!(arr[1..=3], [ 1,2,3 ]);
/// assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]); // This is the `RangeFull`
/// assert_eq!(arr[ .. 3], [0, 1, 2 ]);
/// assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
/// assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
/// assert_eq!(arr[1.. 3], [ 1, 2 ]);
/// assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
/// ```
///
/// [slicing index]: crate::slice::SliceIndex
@ -52,22 +52,26 @@ impl fmt::Debug for RangeFull {
/// A (half-open) range bounded inclusively below and exclusively above
/// (`start..end`).
///
/// The `Range` `start..end` contains all values with `x >= start` and
/// `x < end`. It is empty unless `start < end`.
/// The range `start..end` contains all values with `start <= x < end`.
/// It is empty if `start >= end`.
///
/// # Examples
///
/// The `start..end` syntax is a `Range`:
///
/// ```
/// assert_eq!((3..5), std::ops::Range { start: 3, end: 5 });
/// assert_eq!(3 + 4 + 5, (3..6).sum());
/// ```
///
/// ```
/// let arr = [0, 1, 2, 3, 4];
/// assert_eq!(arr[ .. ], [0,1,2,3,4]);
/// assert_eq!(arr[ .. 3], [0,1,2 ]);
/// assert_eq!(arr[ ..=3], [0,1,2,3 ]);
/// assert_eq!(arr[1.. ], [ 1,2,3,4]);
/// assert_eq!(arr[1.. 3], [ 1,2 ]); // Range
/// assert_eq!(arr[1..=3], [ 1,2,3 ]);
/// assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
/// assert_eq!(arr[ .. 3], [0, 1, 2 ]);
/// assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
/// assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
/// assert_eq!(arr[1.. 3], [ 1, 2 ]); // This is a `Range`
/// assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
/// ```
#[lang = "Range"]
#[doc(alias = "..")]
@ -160,17 +164,21 @@ impl<Idx: PartialOrd<Idx>> Range<Idx> {
///
/// # Examples
///
/// The `start..` syntax is a `RangeFrom`:
///
/// ```
/// assert_eq!((2..), std::ops::RangeFrom { start: 2 });
/// assert_eq!(2 + 3 + 4, (2..).take(3).sum());
/// ```
///
/// ```
/// let arr = [0, 1, 2, 3, 4];
/// assert_eq!(arr[ .. ], [0,1,2,3,4]);
/// assert_eq!(arr[ .. 3], [0,1,2 ]);
/// assert_eq!(arr[ ..=3], [0,1,2,3 ]);
/// assert_eq!(arr[1.. ], [ 1,2,3,4]); // RangeFrom
/// assert_eq!(arr[1.. 3], [ 1,2 ]);
/// assert_eq!(arr[1..=3], [ 1,2,3 ]);
/// assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
/// assert_eq!(arr[ .. 3], [0, 1, 2 ]);
/// assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
/// assert_eq!(arr[1.. ], [ 1, 2, 3, 4]); // This is a `RangeFrom`
/// assert_eq!(arr[1.. 3], [ 1, 2 ]);
/// assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
/// ```
#[lang = "RangeFrom"]
#[doc(alias = "..")]
@ -244,12 +252,12 @@ impl<Idx: PartialOrd<Idx>> RangeFrom<Idx> {
///
/// ```
/// let arr = [0, 1, 2, 3, 4];
/// assert_eq!(arr[ .. ], [0,1,2,3,4]);
/// assert_eq!(arr[ .. 3], [0,1,2 ]); // RangeTo
/// assert_eq!(arr[ ..=3], [0,1,2,3 ]);
/// assert_eq!(arr[1.. ], [ 1,2,3,4]);
/// assert_eq!(arr[1.. 3], [ 1,2 ]);
/// assert_eq!(arr[1..=3], [ 1,2,3 ]);
/// assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
/// assert_eq!(arr[ .. 3], [0, 1, 2 ]); // This is a `RangeTo`
/// assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
/// assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
/// assert_eq!(arr[1.. 3], [ 1, 2 ]);
/// assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
/// ```
///
/// [slicing index]: crate::slice::SliceIndex
@ -310,17 +318,21 @@ impl<Idx: PartialOrd<Idx>> RangeTo<Idx> {
///
/// # Examples
///
/// The `start..=end` syntax is a `RangeInclusive`:
///
/// ```
/// assert_eq!((3..=5), std::ops::RangeInclusive::new(3, 5));
/// assert_eq!(3 + 4 + 5, (3..=5).sum());
/// ```
///
/// ```
/// let arr = [0, 1, 2, 3, 4];
/// assert_eq!(arr[ .. ], [0,1,2,3,4]);
/// assert_eq!(arr[ .. 3], [0,1,2 ]);
/// assert_eq!(arr[ ..=3], [0,1,2,3 ]);
/// assert_eq!(arr[1.. ], [ 1,2,3,4]);
/// assert_eq!(arr[1.. 3], [ 1,2 ]);
/// assert_eq!(arr[1..=3], [ 1,2,3 ]); // RangeInclusive
/// assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
/// assert_eq!(arr[ .. 3], [0, 1, 2 ]);
/// assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]);
/// assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
/// assert_eq!(arr[1.. 3], [ 1, 2 ]);
/// assert_eq!(arr[1..=3], [ 1, 2, 3 ]); // This is a `RangeInclusive`
/// ```
#[lang = "RangeInclusive"]
#[doc(alias = "..=")]
@ -534,12 +546,12 @@ impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> {
///
/// ```
/// let arr = [0, 1, 2, 3, 4];
/// assert_eq!(arr[ .. ], [0,1,2,3,4]);
/// assert_eq!(arr[ .. 3], [0,1,2 ]);
/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); // RangeToInclusive
/// assert_eq!(arr[1.. ], [ 1,2,3,4]);
/// assert_eq!(arr[1.. 3], [ 1,2 ]);
/// assert_eq!(arr[1..=3], [ 1,2,3 ]);
/// assert_eq!(arr[ .. ], [0, 1, 2, 3, 4]);
/// assert_eq!(arr[ .. 3], [0, 1, 2 ]);
/// assert_eq!(arr[ ..=3], [0, 1, 2, 3 ]); // This is a `RangeToInclusive`
/// assert_eq!(arr[1.. ], [ 1, 2, 3, 4]);
/// assert_eq!(arr[1.. 3], [ 1, 2 ]);
/// assert_eq!(arr[1..=3], [ 1, 2, 3 ]);
/// ```
///
/// [slicing index]: crate::slice::SliceIndex
@ -661,9 +673,9 @@ impl<T: Clone> Bound<&T> {
}
}
#[stable(feature = "collections_range", since = "1.28.0")]
/// `RangeBounds` is implemented by Rust's built-in range types, produced
/// by range syntax like `..`, `a..`, `..b`, `..=c`, `d..e`, or `f..=g`.
#[stable(feature = "collections_range", since = "1.28.0")]
pub trait RangeBounds<T: ?Sized> {
/// Start index bound.
///