From e0f8202ed5828670ac5125d3db2adbfb516cca3d Mon Sep 17 00:00:00 2001 From: Trevor Gross Date: Sun, 28 Apr 2024 15:27:36 -0500 Subject: [PATCH] Stabilize `non_null_convenience` Fully stabilize the following API, including const where applicable: impl NonNull { pub const unsafe fn offset(self, count: isize) -> Self; pub const unsafe fn add(self, count: usize) -> Self; pub const unsafe fn sub(self, count: usize) -> Self; pub const unsafe fn offset_from(self, origin: NonNull) -> isize; pub const unsafe fn read(self) -> T; pub unsafe fn read_volatile(self) -> T; pub const unsafe fn read_unaligned(self) -> T; pub unsafe fn write_volatile(self, val: T); pub unsafe fn replace(self, src: T) -> T; } impl NonNull { pub const unsafe fn byte_offset(self, count: isize) -> Self; pub const unsafe fn byte_add(self, count: usize) -> Self; pub const unsafe fn byte_sub(self, count: usize) -> Self; pub const unsafe fn byte_offset_from(self, origin: NonNull) -> isize; pub unsafe fn drop_in_place(self); } Stabilize the following without const: impl NonNull { // const under `const_intrinsic_copy` pub const unsafe fn copy_to(self, dest: NonNull, count: usize); pub const unsafe fn copy_to_nonoverlapping(self, dest: NonNull, count: usize); pub const unsafe fn copy_from(self, src: NonNull, count: usize); pub const unsafe fn copy_from_nonoverlapping(self, src: NonNull, count: usize); // const under `const_ptr_write` pub const unsafe fn write(self, val: T); pub const unsafe fn write_bytes(self, val: u8, count: usize); pub const unsafe fn write_unaligned(self, val: T); // const under `const_swap` pub const unsafe fn swap(self, with: NonNull); // const under `const_align_offset` pub const fn align_offset(self, align: usize) -> usize; // const under `const_pointer_is_aligned` pub const fn is_aligned(self) -> bool; } Left the following unstable: impl NonNull { // moved gate to `ptr_sub_ptr` pub const unsafe fn sub_ptr(self, subtracted: NonNull) -> usize; } impl NonNull { // moved gate to `pointer_is_aligned_to` pub const fn is_aligned_to(self, align: usize) -> bool; } Fixes: https://github.com/rust-lang/rust/issues/117691 --- library/alloc/src/lib.rs | 1 - library/core/src/lib.rs | 1 - library/core/src/ptr/non_null.rs | 140 ++++++++++++++----------------- 3 files changed, 63 insertions(+), 79 deletions(-) diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs index 2bd8fca7e01..4e8792f6fb9 100644 --- a/library/alloc/src/lib.rs +++ b/library/alloc/src/lib.rs @@ -137,7 +137,6 @@ #![feature(maybe_uninit_slice)] #![feature(maybe_uninit_uninit_array)] #![feature(maybe_uninit_uninit_array_transpose)] -#![feature(non_null_convenience)] #![feature(panic_internals)] #![feature(pattern)] #![feature(ptr_internals)] diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs index 19e0ce7099d..cee3870c629 100644 --- a/library/core/src/lib.rs +++ b/library/core/src/lib.rs @@ -180,7 +180,6 @@ #![feature(isqrt)] #![feature(link_cfg)] #![feature(maybe_uninit_uninit_array)] -#![feature(non_null_convenience)] #![feature(offset_of_enum)] #![feature(offset_of_nested)] #![feature(panic_internals)] diff --git a/library/core/src/ptr/non_null.rs b/library/core/src/ptr/non_null.rs index 96ce3cd3a3f..8697b22278f 100644 --- a/library/core/src/ptr/non_null.rs +++ b/library/core/src/ptr/non_null.rs @@ -512,7 +512,6 @@ impl NonNull { /// # Examples /// /// ``` - /// #![feature(non_null_convenience)] /// use std::ptr::NonNull; /// /// let mut s = [1, 2, 3]; @@ -523,12 +522,12 @@ impl NonNull { /// println!("{}", ptr.offset(2).read()); /// } /// ``` - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - #[must_use = "returns a new pointer rather than modifying its argument"] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces - pub const unsafe fn offset(self, count: isize) -> NonNull + #[must_use = "returns a new pointer rather than modifying its argument"] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + pub const unsafe fn offset(self, count: isize) -> Self where T: Sized, { @@ -549,11 +548,11 @@ impl NonNull { /// /// For non-`Sized` pointees this operation changes only the data pointer, /// leaving the metadata untouched. - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[must_use] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn byte_offset(self, count: isize) -> Self { // SAFETY: the caller must uphold the safety contract for `offset` and `byte_offset` has // the same safety contract. @@ -599,7 +598,6 @@ impl NonNull { /// # Examples /// /// ``` - /// #![feature(non_null_convenience)] /// use std::ptr::NonNull; /// /// let s: &str = "123"; @@ -610,11 +608,11 @@ impl NonNull { /// println!("{}", ptr.add(2).read() as char); /// } /// ``` - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - #[must_use = "returns a new pointer rather than modifying its argument"] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[must_use = "returns a new pointer rather than modifying its argument"] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn add(self, count: usize) -> Self where T: Sized, @@ -636,12 +634,12 @@ impl NonNull { /// /// For non-`Sized` pointees this operation changes only the data pointer, /// leaving the metadata untouched. - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[must_use] #[inline(always)] - #[rustc_allow_const_fn_unstable(set_ptr_value)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[rustc_allow_const_fn_unstable(set_ptr_value)] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn byte_add(self, count: usize) -> Self { // SAFETY: the caller must uphold the safety contract for `add` and `byte_add` has the same // safety contract. @@ -688,7 +686,6 @@ impl NonNull { /// # Examples /// /// ``` - /// #![feature(non_null_convenience)] /// use std::ptr::NonNull; /// /// let s: &str = "123"; @@ -699,11 +696,11 @@ impl NonNull { /// println!("{}", end.sub(2).read() as char); /// } /// ``` - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - #[must_use = "returns a new pointer rather than modifying its argument"] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[must_use = "returns a new pointer rather than modifying its argument"] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn sub(self, count: usize) -> Self where T: Sized, @@ -730,12 +727,12 @@ impl NonNull { /// /// For non-`Sized` pointees this operation changes only the data pointer, /// leaving the metadata untouched. - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[must_use] #[inline(always)] - #[rustc_allow_const_fn_unstable(set_ptr_value)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[rustc_allow_const_fn_unstable(set_ptr_value)] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn byte_sub(self, count: usize) -> Self { // SAFETY: the caller must uphold the safety contract for `sub` and `byte_sub` has the same // safety contract. @@ -816,7 +813,6 @@ impl NonNull { /// Basic usage: /// /// ``` - /// #![feature(non_null_convenience)] /// use std::ptr::NonNull; /// /// let a = [0; 5]; @@ -833,7 +829,7 @@ impl NonNull { /// *Incorrect* usage: /// /// ```rust,no_run - /// #![feature(non_null_convenience, strict_provenance)] + /// #![feature(strict_provenance)] /// use std::ptr::NonNull; /// /// let ptr1 = NonNull::new(Box::into_raw(Box::new(0u8))).unwrap(); @@ -845,14 +841,13 @@ impl NonNull { /// // Since ptr2_other and ptr2 are derived from pointers to different objects, /// // computing their offset is undefined behavior, even though /// // they point to the same address! - /// unsafe { - /// let zero = ptr2_other.offset_from(ptr2); // Undefined Behavior - /// } + /// + /// let zero = unsafe { ptr2_other.offset_from(ptr2) }; // Undefined Behavior /// ``` - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn offset_from(self, origin: NonNull) -> isize where T: Sized, @@ -870,10 +865,10 @@ impl NonNull { /// /// For non-`Sized` pointees this operation considers only the data pointers, /// ignoring the metadata. - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn byte_offset_from(self, origin: NonNull) -> isize { // SAFETY: the caller must uphold the safety contract for `byte_offset_from`. unsafe { self.pointer.byte_offset_from(origin.pointer) } @@ -897,7 +892,7 @@ impl NonNull { /// to [`sub`](#method.sub)). The following are all equivalent, assuming /// that their safety preconditions are met: /// ```rust - /// # #![feature(non_null_convenience)] + /// # #![feature(ptr_sub_ptr)] /// # unsafe fn blah(ptr: std::ptr::NonNull, origin: std::ptr::NonNull, count: usize) -> bool { /// ptr.sub_ptr(origin) == count /// # && @@ -926,7 +921,7 @@ impl NonNull { /// # Examples /// /// ``` - /// #![feature(non_null_convenience)] + /// #![feature(ptr_sub_ptr)] /// use std::ptr::NonNull; /// /// let a = [0; 5]; @@ -942,12 +937,10 @@ impl NonNull { /// // This would be incorrect, as the pointers are not correctly ordered: /// // ptr1.sub_ptr(ptr2) /// ``` - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - // #[unstable(feature = "ptr_sub_ptr", issue = "95892")] - // #[rustc_const_unstable(feature = "const_ptr_sub_ptr", issue = "95892")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[unstable(feature = "ptr_sub_ptr", issue = "95892")] + #[rustc_const_unstable(feature = "const_ptr_sub_ptr", issue = "95892")] pub const unsafe fn sub_ptr(self, subtracted: NonNull) -> usize where T: Sized, @@ -962,10 +955,10 @@ impl NonNull { /// See [`ptr::read`] for safety concerns and examples. /// /// [`ptr::read`]: crate::ptr::read() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn read(self) -> T where T: Sized, @@ -984,9 +977,9 @@ impl NonNull { /// See [`ptr::read_volatile`] for safety concerns and examples. /// /// [`ptr::read_volatile`]: crate::ptr::read_volatile() - #[unstable(feature = "non_null_convenience", issue = "117691")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub unsafe fn read_volatile(self) -> T where T: Sized, @@ -1003,10 +996,10 @@ impl NonNull { /// See [`ptr::read_unaligned`] for safety concerns and examples. /// /// [`ptr::read_unaligned`]: crate::ptr::read_unaligned() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub const unsafe fn read_unaligned(self) -> T where T: Sized, @@ -1023,10 +1016,10 @@ impl NonNull { /// See [`ptr::copy`] for safety concerns and examples. /// /// [`ptr::copy`]: crate::ptr::copy() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_intrinsic_copy", issue = "80697")] pub const unsafe fn copy_to(self, dest: NonNull, count: usize) where T: Sized, @@ -1043,10 +1036,10 @@ impl NonNull { /// See [`ptr::copy_nonoverlapping`] for safety concerns and examples. /// /// [`ptr::copy_nonoverlapping`]: crate::ptr::copy_nonoverlapping() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_intrinsic_copy", issue = "80697")] pub const unsafe fn copy_to_nonoverlapping(self, dest: NonNull, count: usize) where T: Sized, @@ -1063,10 +1056,10 @@ impl NonNull { /// See [`ptr::copy`] for safety concerns and examples. /// /// [`ptr::copy`]: crate::ptr::copy() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_intrinsic_copy", issue = "80697")] pub const unsafe fn copy_from(self, src: NonNull, count: usize) where T: Sized, @@ -1083,10 +1076,10 @@ impl NonNull { /// See [`ptr::copy_nonoverlapping`] for safety concerns and examples. /// /// [`ptr::copy_nonoverlapping`]: crate::ptr::copy_nonoverlapping() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_intrinsic_copy", issue = "80697")] pub const unsafe fn copy_from_nonoverlapping(self, src: NonNull, count: usize) where T: Sized, @@ -1100,8 +1093,8 @@ impl NonNull { /// See [`ptr::drop_in_place`] for safety concerns and examples. /// /// [`ptr::drop_in_place`]: crate::ptr::drop_in_place() - #[unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub unsafe fn drop_in_place(self) { // SAFETY: the caller must uphold the safety contract for `drop_in_place`. unsafe { ptr::drop_in_place(self.as_ptr()) } @@ -1113,11 +1106,10 @@ impl NonNull { /// See [`ptr::write`] for safety concerns and examples. /// /// [`ptr::write`]: crate::ptr::write() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - //#[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] pub const unsafe fn write(self, val: T) where T: Sized, @@ -1132,12 +1124,11 @@ impl NonNull { /// See [`ptr::write_bytes`] for safety concerns and examples. /// /// [`ptr::write_bytes`]: crate::ptr::write_bytes() - #[doc(alias = "memset")] - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - //#[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] #[inline(always)] + #[doc(alias = "memset")] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] pub const unsafe fn write_bytes(self, val: u8, count: usize) where T: Sized, @@ -1156,9 +1147,9 @@ impl NonNull { /// See [`ptr::write_volatile`] for safety concerns and examples. /// /// [`ptr::write_volatile`]: crate::ptr::write_volatile() - #[unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub unsafe fn write_volatile(self, val: T) where T: Sized, @@ -1175,11 +1166,10 @@ impl NonNull { /// See [`ptr::write_unaligned`] for safety concerns and examples. /// /// [`ptr::write_unaligned`]: crate::ptr::write_unaligned() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - //#[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] pub const unsafe fn write_unaligned(self, val: T) where T: Sized, @@ -1194,8 +1184,8 @@ impl NonNull { /// See [`ptr::replace`] for safety concerns and examples. /// /// [`ptr::replace`]: crate::ptr::replace() - #[unstable(feature = "non_null_convenience", issue = "117691")] #[inline(always)] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] pub unsafe fn replace(self, src: T) -> T where T: Sized, @@ -1211,10 +1201,9 @@ impl NonNull { /// See [`ptr::swap`] for safety concerns and examples. /// /// [`ptr::swap`]: crate::ptr::swap() - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - //#[rustc_const_unstable(feature = "const_swap", issue = "83163")] #[inline(always)] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_swap", issue = "83163")] pub const unsafe fn swap(self, with: NonNull) where T: Sized, @@ -1246,7 +1235,6 @@ impl NonNull { /// Accessing adjacent `u8` as `u16` /// /// ``` - /// #![feature(non_null_convenience)] /// use std::mem::align_of; /// use std::ptr::NonNull; /// @@ -1264,11 +1252,10 @@ impl NonNull { /// } /// # } /// ``` - #[unstable(feature = "non_null_convenience", issue = "117691")] - #[rustc_const_unstable(feature = "non_null_convenience", issue = "117691")] - //#[rustc_const_unstable(feature = "const_align_offset", issue = "90962")] - #[must_use] #[inline] + #[must_use] + #[stable(feature = "non_null_convenience", since = "CURRENT_RUSTC_VERSION")] + #[rustc_const_unstable(feature = "const_align_offset", issue = "90962")] pub const fn align_offset(self, align: usize) -> usize where T: Sized, @@ -1312,10 +1299,9 @@ impl NonNull { /// underlying allocation. /// /// ``` - /// #![feature(const_pointer_is_aligned)] - /// #![feature(non_null_convenience)] - /// #![feature(const_option)] /// #![feature(const_nonnull_new)] + /// #![feature(const_option)] + /// #![feature(const_pointer_is_aligned)] /// use std::ptr::NonNull; /// /// // On some platforms, the alignment of primitives is less than their size. @@ -1390,10 +1376,10 @@ impl NonNull { /// ``` /// /// [tracking issue]: https://github.com/rust-lang/rust/issues/104203 + #[inline] + #[must_use] #[stable(feature = "pointer_is_aligned", since = "CURRENT_RUSTC_VERSION")] #[rustc_const_unstable(feature = "const_pointer_is_aligned", issue = "104203")] - #[must_use] - #[inline] pub const fn is_aligned(self) -> bool where T: Sized, @@ -1505,10 +1491,10 @@ impl NonNull { /// ``` /// /// [tracking issue]: https://github.com/rust-lang/rust/issues/104203 + #[inline] + #[must_use] #[unstable(feature = "pointer_is_aligned_to", issue = "96284")] #[rustc_const_unstable(feature = "const_pointer_is_aligned", issue = "104203")] - #[must_use] - #[inline] pub const fn is_aligned_to(self, align: usize) -> bool { self.pointer.is_aligned_to(align) }