From fba903a435ea6e0e3736541cb487586262835e48 Mon Sep 17 00:00:00 2001 From: kennytm Date: Fri, 6 Apr 2018 02:03:22 +0800 Subject: [PATCH] Make the fields of RangeInclusive private. Added new()/start()/end() methods to RangeInclusive. Changed the lowering of `..=` to use RangeInclusive::new(). --- src/liballoc/lib.rs | 2 +- src/liballoc/tests/lib.rs | 2 +- src/libcore/ops/range.rs | 60 +++++++++++++++++++++++++++++++++++- src/libcore/tests/lib.rs | 2 +- src/librustc/hir/lowering.rs | 16 +++++++++- src/librustc_trans/lib.rs | 2 +- 6 files changed, 78 insertions(+), 6 deletions(-) diff --git a/src/liballoc/lib.rs b/src/liballoc/lib.rs index 021395d0c82..c94fe2a2f83 100644 --- a/src/liballoc/lib.rs +++ b/src/liballoc/lib.rs @@ -122,7 +122,7 @@ #![feature(on_unimplemented)] #![feature(exact_chunks)] #![feature(pointer_methods)] -#![feature(inclusive_range_fields)] +#![feature(inclusive_range_methods)] #![cfg_attr(stage0, feature(generic_param_attrs))] #![cfg_attr(not(test), feature(fn_traits, i128))] diff --git a/src/liballoc/tests/lib.rs b/src/liballoc/tests/lib.rs index 32272169307..1c8ff316e55 100644 --- a/src/liballoc/tests/lib.rs +++ b/src/liballoc/tests/lib.rs @@ -25,7 +25,7 @@ #![feature(try_reserve)] #![feature(unboxed_closures)] #![feature(exact_chunks)] -#![feature(inclusive_range_fields)] +#![feature(inclusive_range_methods)] extern crate alloc_system; extern crate core; diff --git a/src/libcore/ops/range.rs b/src/libcore/ops/range.rs index d70f7ae66f9..c1bd1ef2d1d 100644 --- a/src/libcore/ops/range.rs +++ b/src/libcore/ops/range.rs @@ -320,7 +320,7 @@ impl> RangeTo { /// ``` /// #![feature(inclusive_range_fields)] /// -/// assert_eq!((3..=5), std::ops::RangeInclusive { start: 3, end: 5 }); +/// assert_eq!((3..=5), std::ops::RangeInclusive::new(3, 5)); /// assert_eq!(3 + 4 + 5, (3..=5).sum()); /// /// let arr = [0, 1, 2, 3]; @@ -331,14 +331,72 @@ impl> RangeTo { #[derive(Clone, PartialEq, Eq, Hash)] // not Copy -- see #27186 #[stable(feature = "inclusive_range", since = "1.26.0")] pub struct RangeInclusive { + // FIXME: The current representation follows RFC 1980, + // but it is known that LLVM is not able to optimize loops following that RFC. + // Consider adding an extra `bool` field to indicate emptiness of the range. + // See #45222 for performance test cases. + #[cfg(not(stage0))] + pub(crate) start: Idx, + #[cfg(not(stage0))] + pub(crate) end: Idx, /// The lower bound of the range (inclusive). + #[cfg(stage0)] #[unstable(feature = "inclusive_range_fields", issue = "49022")] pub start: Idx, /// The upper bound of the range (inclusive). + #[cfg(stage0)] #[unstable(feature = "inclusive_range_fields", issue = "49022")] pub end: Idx, } +impl RangeInclusive { + /// Creates a new inclusive range. Equivalent to writing `start..=end`. + /// + /// # Examples + /// + /// ``` + /// #![feature(inclusive_range_methods)] + /// use std::ops::RangeInclusive; + /// + /// assert_eq!(3..=5, RangeInclusive::new(3, 5)); + /// ``` + #[unstable(feature = "inclusive_range_methods", issue = "49022")] + #[inline] + pub fn new(start: Idx, end: Idx) -> Self { + Self { start, end } + } + + /// Returns the lower bound of the range (inclusive). + /// + /// # Examples + /// + /// ``` + /// #![feature(inclusive_range_methods)] + /// + /// assert_eq!((3..=5).start(), &3); + /// ``` + #[unstable(feature = "inclusive_range_methods", issue = "49022")] + #[inline] + pub fn start(&self) -> &Idx { + &self.start + } + + /// Returns the upper bound of the range (inclusive). + /// + /// # Examples + /// + /// ``` + /// #![feature(inclusive_range_methods)] + /// + /// assert_eq!((3..=5).end(), &5); + /// ``` + #[unstable(feature = "inclusive_range_methods", issue = "49022")] + #[inline] + pub fn end(&self) -> &Idx { + &self.end + } +} + #[stable(feature = "inclusive_range", since = "1.26.0")] impl fmt::Debug for RangeInclusive { fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { diff --git a/src/libcore/tests/lib.rs b/src/libcore/tests/lib.rs index e4d27717938..f6750c590b3 100644 --- a/src/libcore/tests/lib.rs +++ b/src/libcore/tests/lib.rs @@ -44,7 +44,7 @@ #![feature(exact_chunks)] #![cfg_attr(stage0, feature(atomic_nand))] #![feature(reverse_bits)] -#![feature(inclusive_range_fields)] +#![feature(inclusive_range_methods)] #![feature(iterator_find_map)] extern crate core; diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs index e4b9fc1385d..196f7879980 100644 --- a/src/librustc/hir/lowering.rs +++ b/src/librustc/hir/lowering.rs @@ -3119,6 +3119,20 @@ impl<'a> LoweringContext<'a> { ExprKind::Index(ref el, ref er) => { hir::ExprIndex(P(self.lower_expr(el)), P(self.lower_expr(er))) } + // Desugar `..=` to `std::ops::RangeInclusive::new(, )` + ExprKind::Range(Some(ref e1), Some(ref e2), RangeLimits::Closed) => { + // FIXME: Use head_sp directly after RangeInclusive::new() is stabilized in stage0. + let span = self.allow_internal_unstable(CompilerDesugaringKind::DotFill, e.span); + let id = self.lower_node_id(e.id); + let e1 = self.lower_expr(e1); + let e2 = self.lower_expr(e2); + let ty_path = P(self.std_path(span, &["ops", "RangeInclusive"], false)); + let ty = self.ty_path(id, span, hir::QPath::Resolved(None, ty_path)); + let new_seg = P(hir::PathSegment::from_name(Symbol::intern("new"))); + let new_path = hir::QPath::TypeRelative(ty, new_seg); + let new = P(self.expr(span, hir::ExprPath(new_path), ThinVec::new())); + hir::ExprCall(new, hir_vec![e1, e2]) + } ExprKind::Range(ref e1, ref e2, lims) => { use syntax::ast::RangeLimits::*; @@ -3128,7 +3142,7 @@ impl<'a> LoweringContext<'a> { (&None, &Some(..), HalfOpen) => "RangeTo", (&Some(..), &Some(..), HalfOpen) => "Range", (&None, &Some(..), Closed) => "RangeToInclusive", - (&Some(..), &Some(..), Closed) => "RangeInclusive", + (&Some(..), &Some(..), Closed) => unreachable!(), (_, &None, Closed) => self.diagnostic() .span_fatal(e.span, "inclusive range with no end") .raise(), diff --git a/src/librustc_trans/lib.rs b/src/librustc_trans/lib.rs index 96a10e8b99d..9259fef279f 100644 --- a/src/librustc_trans/lib.rs +++ b/src/librustc_trans/lib.rs @@ -29,7 +29,7 @@ #![feature(rustc_diagnostic_macros)] #![feature(slice_sort_by_cached_key)] #![feature(optin_builtin_traits)] -#![feature(inclusive_range_fields)] +#![feature(inclusive_range_methods)] use rustc::dep_graph::WorkProduct; use syntax_pos::symbol::Symbol;