rust/src/libstd/tuple.rs
Patrick Walton 8693943676 librustc: Ensure that type parameters are in the right positions in paths.
This removes the stacking of type parameters that occurs when invoking
trait methods, and fixes all places in the standard library that were
relying on it. It is somewhat awkward in places; I think we'll probably
want something like the `Foo::<for T>::new()` syntax.
2013-08-27 18:47:57 -07:00

434 lines
15 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
#[allow(missing_doc)];
use clone::Clone;
pub use self::inner::*;
/// Method extensions to pairs where both types satisfy the `Clone` bound
pub trait CopyableTuple<T, U> {
/// Return the first element of self
fn first(&self) -> T;
/// Return the second element of self
fn second(&self) -> U;
/// Return the results of swapping the two elements of self
fn swap(&self) -> (U, T);
}
impl<T:Clone,U:Clone> CopyableTuple<T, U> for (T, U) {
/// Return the first element of self
#[inline]
fn first(&self) -> T {
match *self {
(ref t, _) => (*t).clone(),
}
}
/// Return the second element of self
#[inline]
fn second(&self) -> U {
match *self {
(_, ref u) => (*u).clone(),
}
}
/// Return the results of swapping the two elements of self
#[inline]
fn swap(&self) -> (U, T) {
match (*self).clone() {
(t, u) => (u, t),
}
}
}
/// Method extensions for pairs where the types don't necessarily satisfy the
/// `Clone` bound
pub trait ImmutableTuple<T, U> {
/// Return a reference to the first element of self
fn first_ref<'a>(&'a self) -> &'a T;
/// Return a reference to the second element of self
fn second_ref<'a>(&'a self) -> &'a U;
}
impl<T, U> ImmutableTuple<T, U> for (T, U) {
#[inline]
fn first_ref<'a>(&'a self) -> &'a T {
match *self {
(ref t, _) => t,
}
}
#[inline]
fn second_ref<'a>(&'a self) -> &'a U {
match *self {
(_, ref u) => u,
}
}
}
// macro for implementing n-ary tuple functions and operations
macro_rules! tuple_impls {
($(
($cloneable_trait:ident, $immutable_trait:ident) {
$(($get_fn:ident, $get_ref_fn:ident) -> $T:ident {
$get_pattern:pat => $ret:expr
})+
}
)+) => {
pub mod inner {
use clone::Clone;
#[cfg(not(test))] use cmp::*;
#[cfg(not(test))] use num::Zero;
$(
pub trait $cloneable_trait<$($T),+> {
$(fn $get_fn(&self) -> $T;)+
}
impl<$($T:Clone),+> $cloneable_trait<$($T),+> for ($($T,)+) {
$(
#[inline]
fn $get_fn(&self) -> $T {
self.$get_ref_fn().clone()
}
)+
}
pub trait $immutable_trait<$($T),+> {
$(fn $get_ref_fn<'a>(&'a self) -> &'a $T;)+
}
impl<$($T),+> $immutable_trait<$($T),+> for ($($T,)+) {
$(
#[inline]
fn $get_ref_fn<'a>(&'a self) -> &'a $T {
match *self { $get_pattern => $ret }
}
)+
}
impl<$($T:Clone),+> Clone for ($($T,)+) {
fn clone(&self) -> ($($T,)+) {
($(self.$get_ref_fn().clone(),)+)
}
}
#[cfg(not(test))]
impl<$($T:Eq),+> Eq for ($($T,)+) {
#[inline]
fn eq(&self, other: &($($T,)+)) -> bool {
$(*self.$get_ref_fn() == *other.$get_ref_fn())&&+
}
#[inline]
fn ne(&self, other: &($($T,)+)) -> bool {
$(*self.$get_ref_fn() != *other.$get_ref_fn())||+
}
}
#[cfg(not(test))]
impl<$($T:TotalEq),+> TotalEq for ($($T,)+) {
#[inline]
fn equals(&self, other: &($($T,)+)) -> bool {
$(self.$get_ref_fn().equals(other.$get_ref_fn()))&&+
}
}
#[cfg(not(test))]
impl<$($T:Ord + Eq),+> Ord for ($($T,)+) {
#[inline]
fn lt(&self, other: &($($T,)+)) -> bool {
lexical_ord!(lt, $(self.$get_ref_fn(), other.$get_ref_fn()),+)
}
#[inline]
fn le(&self, other: &($($T,)+)) -> bool {
lexical_ord!(le, $(self.$get_ref_fn(), other.$get_ref_fn()),+)
}
#[inline]
fn ge(&self, other: &($($T,)+)) -> bool {
lexical_ord!(ge, $(self.$get_ref_fn(), other.$get_ref_fn()),+)
}
#[inline]
fn gt(&self, other: &($($T,)+)) -> bool {
lexical_ord!(gt, $(self.$get_ref_fn(), other.$get_ref_fn()),+)
}
}
#[cfg(not(test))]
impl<$($T:TotalOrd),+> TotalOrd for ($($T,)+) {
#[inline]
fn cmp(&self, other: &($($T,)+)) -> Ordering {
lexical_cmp!($(self.$get_ref_fn(), other.$get_ref_fn()),+)
}
}
#[cfg(not(test))]
impl<$($T:Zero),+> Zero for ($($T,)+) {
#[inline]
fn zero() -> ($($T,)+) {
($({ let x: $T = Zero::zero(); x},)+)
}
#[inline]
fn is_zero(&self) -> bool {
$(self.$get_ref_fn().is_zero())&&+
}
}
)+
}
}
}
// 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! {
(CloneableTuple1, ImmutableTuple1) {
(n0, n0_ref) -> A { (ref a,) => a }
}
(CloneableTuple2, ImmutableTuple2) {
(n0, n0_ref) -> A { (ref a,_) => a }
(n1, n1_ref) -> B { (_,ref b) => b }
}
(CloneableTuple3, ImmutableTuple3) {
(n0, n0_ref) -> A { (ref a,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_) => b }
(n2, n2_ref) -> C { (_,_,ref c) => c }
}
(CloneableTuple4, ImmutableTuple4) {
(n0, n0_ref) -> A { (ref a,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d) => d }
}
(CloneableTuple5, ImmutableTuple5) {
(n0, n0_ref) -> A { (ref a,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e) => e }
}
(CloneableTuple6, ImmutableTuple6) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f) => f }
}
(CloneableTuple7, ImmutableTuple7) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f,_) => f }
(n6, n6_ref) -> G { (_,_,_,_,_,_,ref g) => g }
}
(CloneableTuple8, ImmutableTuple8) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_,_,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f,_,_) => f }
(n6, n6_ref) -> G { (_,_,_,_,_,_,ref g,_) => g }
(n7, n7_ref) -> H { (_,_,_,_,_,_,_,ref h) => h }
}
(CloneableTuple9, ImmutableTuple9) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_,_,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_,_,_,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f,_,_,_) => f }
(n6, n6_ref) -> G { (_,_,_,_,_,_,ref g,_,_) => g }
(n7, n7_ref) -> H { (_,_,_,_,_,_,_,ref h,_) => h }
(n8, n8_ref) -> I { (_,_,_,_,_,_,_,_,ref i) => i }
}
(CloneableTuple10, ImmutableTuple10) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_,_,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_,_,_,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_,_,_,_,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f,_,_,_,_) => f }
(n6, n6_ref) -> G { (_,_,_,_,_,_,ref g,_,_,_) => g }
(n7, n7_ref) -> H { (_,_,_,_,_,_,_,ref h,_,_) => h }
(n8, n8_ref) -> I { (_,_,_,_,_,_,_,_,ref i,_) => i }
(n9, n9_ref) -> J { (_,_,_,_,_,_,_,_,_,ref j) => j }
}
(CloneableTuple11, ImmutableTuple11) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_,_,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_,_,_,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_,_,_,_,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_,_,_,_,_,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f,_,_,_,_,_) => f }
(n6, n6_ref) -> G { (_,_,_,_,_,_,ref g,_,_,_,_) => g }
(n7, n7_ref) -> H { (_,_,_,_,_,_,_,ref h,_,_,_) => h }
(n8, n8_ref) -> I { (_,_,_,_,_,_,_,_,ref i,_,_) => i }
(n9, n9_ref) -> J { (_,_,_,_,_,_,_,_,_,ref j,_) => j }
(n10, n10_ref) -> K { (_,_,_,_,_,_,_,_,_,_,ref k) => k }
}
(CloneableTuple12, ImmutableTuple12) {
(n0, n0_ref) -> A { (ref a,_,_,_,_,_,_,_,_,_,_,_) => a }
(n1, n1_ref) -> B { (_,ref b,_,_,_,_,_,_,_,_,_,_) => b }
(n2, n2_ref) -> C { (_,_,ref c,_,_,_,_,_,_,_,_,_) => c }
(n3, n3_ref) -> D { (_,_,_,ref d,_,_,_,_,_,_,_,_) => d }
(n4, n4_ref) -> E { (_,_,_,_,ref e,_,_,_,_,_,_,_) => e }
(n5, n5_ref) -> F { (_,_,_,_,_,ref f,_,_,_,_,_,_) => f }
(n6, n6_ref) -> G { (_,_,_,_,_,_,ref g,_,_,_,_,_) => g }
(n7, n7_ref) -> H { (_,_,_,_,_,_,_,ref h,_,_,_,_) => h }
(n8, n8_ref) -> I { (_,_,_,_,_,_,_,_,ref i,_,_,_) => i }
(n9, n9_ref) -> J { (_,_,_,_,_,_,_,_,_,ref j,_,_) => j }
(n10, n10_ref) -> K { (_,_,_,_,_,_,_,_,_,_,ref k,_) => k }
(n11, n11_ref) -> L { (_,_,_,_,_,_,_,_,_,_,_,ref l) => l }
}
}
#[cfg(test)]
mod tests {
use super::*;
use clone::Clone;
use cmp::*;
#[test]
fn test_tuple_ref() {
let x = (~"foo", ~"bar");
assert_eq!(x.first_ref(), &~"foo");
assert_eq!(x.second_ref(), &~"bar");
}
#[test]
fn test_tuple() {
assert_eq!((948, 4039.48).first(), 948);
assert_eq!((34.5, ~"foo").second(), ~"foo");
assert_eq!(('a', 2).swap(), (2, 'a'));
}
#[test]
fn test_clone() {
let a = (1, ~"2");
let b = a.clone();
assert_eq!(a.first(), b.first());
assert_eq!(a.second(), b.second());
}
#[test]
fn test_n_tuple() {
let t = (0u8, 1u16, 2u32, 3u64, 4u, 5i8, 6i16, 7i32, 8i64, 9i, 10f32, 11f64);
assert_eq!(t.n0(), 0u8);
assert_eq!(t.n1(), 1u16);
assert_eq!(t.n2(), 2u32);
assert_eq!(t.n3(), 3u64);
assert_eq!(t.n4(), 4u);
assert_eq!(t.n5(), 5i8);
assert_eq!(t.n6(), 6i16);
assert_eq!(t.n7(), 7i32);
assert_eq!(t.n8(), 8i64);
assert_eq!(t.n9(), 9i);
assert_eq!(t.n10(), 10f32);
assert_eq!(t.n11(), 11f64);
assert_eq!(t.n0_ref(), &0u8);
assert_eq!(t.n1_ref(), &1u16);
assert_eq!(t.n2_ref(), &2u32);
assert_eq!(t.n3_ref(), &3u64);
assert_eq!(t.n4_ref(), &4u);
assert_eq!(t.n5_ref(), &5i8);
assert_eq!(t.n6_ref(), &6i16);
assert_eq!(t.n7_ref(), &7i32);
assert_eq!(t.n8_ref(), &8i64);
assert_eq!(t.n9_ref(), &9i);
assert_eq!(t.n10_ref(), &10f32);
assert_eq!(t.n11_ref(), &11f64);
}
#[test]
fn test_tuple_cmp() {
let (small, big) = ((1u, 2u, 3u), (3u, 2u, 1u));
let nan = 0.0/0.0;
// Eq
assert_eq!(small, small);
assert_eq!(big, big);
assert!(small != big);
assert!(big != small);
// Ord
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)));
// TotalEq
assert!(small.equals(&small));
assert!(big.equals(&big));
assert!(!small.equals(&big));
assert!(!big.equals(&small));
// TotalOrd
assert_eq!(small.cmp(&small), Equal);
assert_eq!(big.cmp(&big), Equal);
assert_eq!(small.cmp(&big), Less);
assert_eq!(big.cmp(&small), Greater);
}
}