rust-bitcoin-unsafe-fast/internals/src/macros.rs

116 lines
3.4 KiB
Rust

// SPDX-License-Identifier: CC0-1.0
//! Various macros used by the Rust Bitcoin ecosystem.
//!
/// Implements standard array methods for a given wrapper type.
#[macro_export]
macro_rules! impl_array_newtype {
($thing:ident, $ty:ty, $len:literal) => {
impl $thing {
/// Converts the object to a raw pointer.
#[inline]
pub fn as_ptr(&self) -> *const $ty {
let &$thing(ref dat) = self;
dat.as_ptr()
}
/// Converts the object to a mutable raw pointer.
#[inline]
pub fn as_mut_ptr(&mut self) -> *mut $ty {
let &mut $thing(ref mut dat) = self;
dat.as_mut_ptr()
}
/// Returns the length of the object as an array.
#[inline]
pub fn len(&self) -> usize { $len }
/// Returns whether the object, as an array, is empty. Always false.
#[inline]
pub fn is_empty(&self) -> bool { false }
}
impl<'a> core::convert::From<[$ty; $len]> for $thing {
fn from(data: [$ty; $len]) -> Self { $thing(data) }
}
impl<'a> core::convert::From<&'a [$ty; $len]> for $thing {
fn from(data: &'a [$ty; $len]) -> Self { $thing(*data) }
}
impl<'a> core::convert::TryFrom<&'a [$ty]> for $thing {
type Error = core::array::TryFromSliceError;
fn try_from(data: &'a [$ty]) -> Result<Self, Self::Error> {
use core::convert::TryInto;
Ok($thing(data.try_into()?))
}
}
impl AsRef<[$ty; $len]> for $thing {
fn as_ref(&self) -> &[$ty; $len] { &self.0 }
}
impl AsMut<[$ty; $len]> for $thing {
fn as_mut(&mut self) -> &mut [$ty; $len] { &mut self.0 }
}
impl AsRef<[$ty]> for $thing {
fn as_ref(&self) -> &[$ty] { &self.0 }
}
impl AsMut<[$ty]> for $thing {
fn as_mut(&mut self) -> &mut [$ty] { &mut self.0 }
}
impl core::borrow::Borrow<[$ty; $len]> for $thing {
fn borrow(&self) -> &[$ty; $len] { &self.0 }
}
impl core::borrow::BorrowMut<[$ty; $len]> for $thing {
fn borrow_mut(&mut self) -> &mut [$ty; $len] { &mut self.0 }
}
// The following two are valid because `[T; N]: Borrow<[T]>`
impl core::borrow::Borrow<[$ty]> for $thing {
fn borrow(&self) -> &[$ty] { &self.0 }
}
impl core::borrow::BorrowMut<[$ty]> for $thing {
fn borrow_mut(&mut self) -> &mut [$ty] { &mut self.0 }
}
impl<I> core::ops::Index<I> for $thing
where
[$ty]: core::ops::Index<I>,
{
type Output = <[$ty] as core::ops::Index<I>>::Output;
#[inline]
fn index(&self, index: I) -> &Self::Output { &self.0[index] }
}
};
}
/// Implements `Debug` by calling through to `Display`.
#[macro_export]
macro_rules! debug_from_display {
($thing:ident) => {
impl core::fmt::Debug for $thing {
fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
core::fmt::Display::fmt(self, f)
}
}
};
}
/// Asserts a boolean expression at compile time.
#[macro_export]
macro_rules! const_assert {
($x:expr) => {{
const _: [(); 0 - !$x as usize] = [];
}};
}