rust/src/libcore/tuple.rs
Alex Crichton bba701c59d std: Drop Total from Total{Eq,Ord}
This completes the last stage of the renaming of the comparison hierarchy of
traits. This change renames TotalEq to Eq and TotalOrd to Ord.

In the future the new Eq/Ord will be filled out with their appropriate methods,
but for now this change is purely a renaming change.

[breaking-change]
2014-06-01 10:31:27 -07:00

384 lines
14 KiB
Rust

// Copyright 2012 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! Operations on tuples
//!
//! To access a single element of a tuple one can use the following
//! methods:
//!
//! * `valN` - returns a value of _N_-th element
//! * `refN` - returns a reference to _N_-th element
//! * `mutN` - returns a mutable reference to _N_-th element
//!
//! Indexing starts from zero, so `val0` returns first value, `val1`
//! returns second value, and so on. In general, a tuple with _S_
//! elements provides aforementioned methods suffixed with numbers
//! from `0` to `S-1`. Traits which contain these methods are
//! implemented for tuples with up to 12 elements.
//!
//! If every type inside a tuple implements one of the following
//! traits, then a tuple itself also implements it.
//!
//! * `Clone`
//! * `PartialEq`
//! * `Eq`
//! * `PartialOrd`
//! * `Ord`
//! * `Default`
//!
//! # Examples
//!
//! Using methods:
//!
//! ```
//! let pair = ("pi", 3.14);
//! assert_eq!(pair.val0(), "pi");
//! assert_eq!(pair.val1(), 3.14);
//! ```
//!
//! Using traits implemented for tuples:
//!
//! ```
//! use std::default::Default;
//!
//! let a = (1, 2);
//! let b = (3, 4);
//! assert!(a != b);
//!
//! let c = b.clone();
//! assert!(b == c);
//!
//! let d : (u32, f32) = Default::default();
//! assert_eq!(d, (0u32, 0.0f32));
//! ```
#![doc(primitive = "tuple")]
use clone::Clone;
#[cfg(not(test))] use cmp::*;
#[cfg(not(test))] use default::Default;
// macro for implementing n-ary tuple functions and operations
macro_rules! tuple_impls {
($(
$Tuple:ident {
$(($valN:ident, $refN:ident, $mutN:ident) -> $T:ident {
($($x:ident),+) => $ret:expr
})+
}
)+) => {
$(
#[allow(missing_doc)]
pub trait $Tuple<$($T),+> {
$(fn $valN(self) -> $T;)+
$(fn $refN<'a>(&'a self) -> &'a $T;)+
$(fn $mutN<'a>(&'a mut self) -> &'a mut $T;)+
}
impl<$($T),+> $Tuple<$($T),+> for ($($T,)+) {
$(
#[inline]
#[allow(unused_variable)]
fn $valN(self) -> $T {
let ($($x,)+) = self; $ret
}
#[inline]
#[allow(unused_variable)]
fn $refN<'a>(&'a self) -> &'a $T {
let ($(ref $x,)+) = *self; $ret
}
#[inline]
#[allow(unused_variable)]
fn $mutN<'a>(&'a mut self) -> &'a mut $T {
let ($(ref mut $x,)+) = *self; $ret
}
)+
}
impl<$($T:Clone),+> Clone for ($($T,)+) {
fn clone(&self) -> ($($T,)+) {
($(self.$refN().clone(),)+)
}
}
#[cfg(not(test))]
impl<$($T:PartialEq),+> PartialEq for ($($T,)+) {
#[inline]
fn eq(&self, other: &($($T,)+)) -> bool {
$(*self.$refN() == *other.$refN())&&+
}
#[inline]
fn ne(&self, other: &($($T,)+)) -> bool {
$(*self.$refN() != *other.$refN())||+
}
}
#[cfg(not(test))]
impl<$($T:Eq),+> Eq for ($($T,)+) {}
#[cfg(not(test))]
impl<$($T:PartialOrd + PartialEq),+> PartialOrd for ($($T,)+) {
#[inline]
fn lt(&self, other: &($($T,)+)) -> bool {
lexical_ord!(lt, $(self.$refN(), other.$refN()),+)
}
#[inline]
fn le(&self, other: &($($T,)+)) -> bool {
lexical_ord!(le, $(self.$refN(), other.$refN()),+)
}
#[inline]
fn ge(&self, other: &($($T,)+)) -> bool {
lexical_ord!(ge, $(self.$refN(), other.$refN()),+)
}
#[inline]
fn gt(&self, other: &($($T,)+)) -> bool {
lexical_ord!(gt, $(self.$refN(), other.$refN()),+)
}
}
#[cfg(not(test))]
impl<$($T:Ord),+> Ord for ($($T,)+) {
#[inline]
fn cmp(&self, other: &($($T,)+)) -> Ordering {
lexical_cmp!($(self.$refN(), other.$refN()),+)
}
}
#[cfg(not(test))]
impl<$($T:Default),+> Default for ($($T,)+) {
#[inline]
fn default() -> ($($T,)+) {
($({ let x: $T = Default::default(); x},)+)
}
}
)+
}
}
// Constructs an expression that performs a lexical ordering using method $rel.
// The values are interleaved, so the macro invocation for
// `(a1, a2, a3) < (b1, b2, b3)` would be `lexical_ord!(lt, a1, b1, a2, b2,
// a3, b3)` (and similarly for `lexical_cmp`)
macro_rules! lexical_ord {
($rel: ident, $a:expr, $b:expr, $($rest_a:expr, $rest_b:expr),+) => {
if *$a != *$b { lexical_ord!($rel, $a, $b) }
else { lexical_ord!($rel, $($rest_a, $rest_b),+) }
};
($rel: ident, $a:expr, $b:expr) => { (*$a) . $rel ($b) };
}
macro_rules! lexical_cmp {
($a:expr, $b:expr, $($rest_a:expr, $rest_b:expr),+) => {
match ($a).cmp($b) {
Equal => lexical_cmp!($($rest_a, $rest_b),+),
ordering => ordering
}
};
($a:expr, $b:expr) => { ($a).cmp($b) };
}
tuple_impls! {
Tuple1 {
(val0, ref0, mut0) -> A { (a) => a }
}
Tuple2 {
(val0, ref0, mut0) -> A { (a, b) => a }
(val1, ref1, mut1) -> B { (a, b) => b }
}
Tuple3 {
(val0, ref0, mut0) -> A { (a, b, c) => a }
(val1, ref1, mut1) -> B { (a, b, c) => b }
(val2, ref2, mut2) -> C { (a, b, c) => c }
}
Tuple4 {
(val0, ref0, mut0) -> A { (a, b, c, d) => a }
(val1, ref1, mut1) -> B { (a, b, c, d) => b }
(val2, ref2, mut2) -> C { (a, b, c, d) => c }
(val3, ref3, mut3) -> D { (a, b, c, d) => d }
}
Tuple5 {
(val0, ref0, mut0) -> A { (a, b, c, d, e) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e) => e }
}
Tuple6 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f) => f }
}
Tuple7 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f, g) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f, g) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f, g) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f, g) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f, g) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f, g) => f }
(val6, ref6, mut6) -> G { (a, b, c, d, e, f, g) => g }
}
Tuple8 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f, g, h) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f, g, h) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f, g, h) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f, g, h) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f, g, h) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f, g, h) => f }
(val6, ref6, mut6) -> G { (a, b, c, d, e, f, g, h) => g }
(val7, ref7, mut7) -> H { (a, b, c, d, e, f, g, h) => h }
}
Tuple9 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f, g, h, i) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f, g, h, i) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f, g, h, i) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f, g, h, i) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f, g, h, i) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f, g, h, i) => f }
(val6, ref6, mut6) -> G { (a, b, c, d, e, f, g, h, i) => g }
(val7, ref7, mut7) -> H { (a, b, c, d, e, f, g, h, i) => h }
(val8, ref8, mut8) -> I { (a, b, c, d, e, f, g, h, i) => i }
}
Tuple10 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f, g, h, i, j) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f, g, h, i, j) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f, g, h, i, j) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f, g, h, i, j) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f, g, h, i, j) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f, g, h, i, j) => f }
(val6, ref6, mut6) -> G { (a, b, c, d, e, f, g, h, i, j) => g }
(val7, ref7, mut7) -> H { (a, b, c, d, e, f, g, h, i, j) => h }
(val8, ref8, mut8) -> I { (a, b, c, d, e, f, g, h, i, j) => i }
(val9, ref9, mut9) -> J { (a, b, c, d, e, f, g, h, i, j) => j }
}
Tuple11 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f, g, h, i, j, k) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f, g, h, i, j, k) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f, g, h, i, j, k) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f, g, h, i, j, k) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f, g, h, i, j, k) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f, g, h, i, j, k) => f }
(val6, ref6, mut6) -> G { (a, b, c, d, e, f, g, h, i, j, k) => g }
(val7, ref7, mut7) -> H { (a, b, c, d, e, f, g, h, i, j, k) => h }
(val8, ref8, mut8) -> I { (a, b, c, d, e, f, g, h, i, j, k) => i }
(val9, ref9, mut9) -> J { (a, b, c, d, e, f, g, h, i, j, k) => j }
(val10, ref10, mut10) -> K { (a, b, c, d, e, f, g, h, i, j, k) => k }
}
Tuple12 {
(val0, ref0, mut0) -> A { (a, b, c, d, e, f, g, h, i, j, k, l) => a }
(val1, ref1, mut1) -> B { (a, b, c, d, e, f, g, h, i, j, k, l) => b }
(val2, ref2, mut2) -> C { (a, b, c, d, e, f, g, h, i, j, k, l) => c }
(val3, ref3, mut3) -> D { (a, b, c, d, e, f, g, h, i, j, k, l) => d }
(val4, ref4, mut4) -> E { (a, b, c, d, e, f, g, h, i, j, k, l) => e }
(val5, ref5, mut5) -> F { (a, b, c, d, e, f, g, h, i, j, k, l) => f }
(val6, ref6, mut6) -> G { (a, b, c, d, e, f, g, h, i, j, k, l) => g }
(val7, ref7, mut7) -> H { (a, b, c, d, e, f, g, h, i, j, k, l) => h }
(val8, ref8, mut8) -> I { (a, b, c, d, e, f, g, h, i, j, k, l) => i }
(val9, ref9, mut9) -> J { (a, b, c, d, e, f, g, h, i, j, k, l) => j }
(val10, ref10, mut10) -> K { (a, b, c, d, e, f, g, h, i, j, k, l) => k }
(val11, ref11, mut11) -> L { (a, b, c, d, e, f, g, h, i, j, k, l) => l }
}
}
#[cfg(test)]
mod tests {
use super::*;
use clone::Clone;
use cmp::*;
use realstd::str::Str;
#[test]
fn test_clone() {
let a = (1, "2");
let b = a.clone();
assert_eq!(a, b);
}
#[test]
fn test_getters() {
macro_rules! test_getter(
($x:expr, $valN:ident, $refN:ident, $mutN:ident,
$init:expr, $incr:expr, $result:expr) => ({
assert_eq!($x.$valN(), $init);
assert_eq!(*$x.$refN(), $init);
*$x.$mutN() += $incr;
assert_eq!(*$x.$refN(), $result);
})
)
let mut x = (0u8, 1u16, 2u32, 3u64, 4u, 5i8, 6i16, 7i32, 8i64, 9i, 10f32, 11f64);
test_getter!(x, val0, ref0, mut0, 0, 1, 1);
test_getter!(x, val1, ref1, mut1, 1, 1, 2);
test_getter!(x, val2, ref2, mut2, 2, 1, 3);
test_getter!(x, val3, ref3, mut3, 3, 1, 4);
test_getter!(x, val4, ref4, mut4, 4, 1, 5);
test_getter!(x, val5, ref5, mut5, 5, 1, 6);
test_getter!(x, val6, ref6, mut6, 6, 1, 7);
test_getter!(x, val7, ref7, mut7, 7, 1, 8);
test_getter!(x, val8, ref8, mut8, 8, 1, 9);
test_getter!(x, val9, ref9, mut9, 9, 1, 10);
test_getter!(x, val10, ref10, mut10, 10.0, 1.0, 11.0);
test_getter!(x, val11, ref11, mut11, 11.0, 1.0, 12.0);
}
#[test]
fn test_tuple_cmp() {
let (small, big) = ((1u, 2u, 3u), (3u, 2u, 1u));
let nan = 0.0/0.0;
// PartialEq
assert_eq!(small, small);
assert_eq!(big, big);
assert!(small != big);
assert!(big != small);
// PartialOrd
assert!(small < big);
assert!(!(small < small));
assert!(!(big < small));
assert!(!(big < big));
assert!(small <= small);
assert!(big <= big);
assert!(big > small);
assert!(small >= small);
assert!(big >= small);
assert!(big >= big);
assert!(!((1.0, 2.0) < (nan, 3.0)));
assert!(!((1.0, 2.0) <= (nan, 3.0)));
assert!(!((1.0, 2.0) > (nan, 3.0)));
assert!(!((1.0, 2.0) >= (nan, 3.0)));
assert!(((1.0, 2.0) < (2.0, nan)));
assert!(!((2.0, 2.0) < (2.0, nan)));
// Ord
assert!(small.cmp(&small) == Equal);
assert!(big.cmp(&big) == Equal);
assert!(small.cmp(&big) == Less);
assert!(big.cmp(&small) == Greater);
}
#[test]
fn test_show() {
let s = format!("{}", (1,));
assert_eq!(s.as_slice(), "(1,)");
let s = format!("{}", (1, true));
assert_eq!(s.as_slice(), "(1, true)");
let s = format!("{}", (1, "hi", true));
assert_eq!(s.as_slice(), "(1, hi, true)");
}
}