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rust/src/libcore/vec.rs
Brian Anderson b355936b4d Convert ret to return
2012-08-01 19:16:06 -07:00

2565 lines
70 KiB
Rust
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//! Vectors
import option::{some, none};
import ptr::addr_of;
import libc::size_t;
export append;
export append_one;
export consume;
export init_op;
export is_empty;
export is_not_empty;
export same_length;
export reserve;
export reserve_at_least;
export capacity;
export len;
export from_fn;
export from_elem;
export build, build_sized;
export to_mut;
export from_mut;
export head;
export tail;
export tailn;
export init;
export last;
export last_opt;
export slice;
export view, mut_view, const_view;
export split;
export splitn;
export rsplit;
export rsplitn;
export shift;
export unshift;
export pop;
export push, push_all, push_all_move;
export grow;
export grow_fn;
export grow_set;
export map;
export mapi;
export map2;
export map_consume;
export flat_map;
export filter_map;
export filter;
export concat;
export connect;
export foldl;
export foldr;
export any;
export any2;
export all;
export alli;
export all2;
export contains;
export count;
export find;
export find_between;
export rfind;
export rfind_between;
export position_elem;
export position;
export position_between;
export position_elem;
export rposition;
export rposition_between;
export unzip;
export zip;
export swap;
export reverse;
export reversed;
export iter, iter_between, each, eachi, reach, reachi;
export iter2;
export iteri;
export riter;
export riteri;
export permute;
export windowed;
export as_buf;
export as_mut_buf;
export as_const_buf;
export unsafe;
export u8;
export extensions;
export const_vector;
export copyable_vector;
export immutable_vector;
export immutable_copyable_vector;
export iter_trait_extensions;
export vec_concat;
#[abi = "cdecl"]
extern mod rustrt {
fn vec_reserve_shared(++t: *sys::type_desc,
++v: **unsafe::vec_repr,
++n: libc::size_t);
fn vec_from_buf_shared(++t: *sys::type_desc,
++ptr: *(),
++count: libc::size_t) -> *unsafe::vec_repr;
}
#[abi = "rust-intrinsic"]
extern mod rusti {
fn move_val_init<T>(&dst: T, -src: T);
}
/// A function used to initialize the elements of a vector
type init_op<T> = fn(uint) -> T;
/// Returns true if a vector contains no elements
pure fn is_empty<T>(v: &[const T]) -> bool {
as_const_buf(v, |_p, len| len == 0u)
}
/// Returns true if a vector contains some elements
pure fn is_not_empty<T>(v: &[const T]) -> bool {
as_const_buf(v, |_p, len| len > 0u)
}
/// Returns true if two vectors have the same length
pure fn same_length<T, U>(xs: &[const T], ys: &[const U]) -> bool {
len(xs) == len(ys)
}
/**
* Reserves capacity for exactly `n` elements in the given vector.
*
* If the capacity for `v` is already equal to or greater than the requested
* capacity, then no action is taken.
*
* # Arguments
*
* * v - A vector
* * n - The number of elements to reserve space for
*/
fn reserve<T>(&v: ~[const T], n: uint) {
// Only make the (slow) call into the runtime if we have to
if capacity(v) < n {
let ptr = ptr::addr_of(v) as **unsafe::vec_repr;
rustrt::vec_reserve_shared(sys::get_type_desc::<T>(),
ptr, n as size_t);
}
}
/**
* Reserves capacity for at least `n` elements in the given vector.
*
* This function will over-allocate in order to amortize the allocation costs
* in scenarios where the caller may need to repeatedly reserve additional
* space.
*
* If the capacity for `v` is already equal to or greater than the requested
* capacity, then no action is taken.
*
* # Arguments
*
* * v - A vector
* * n - The number of elements to reserve space for
*/
fn reserve_at_least<T>(&v: ~[const T], n: uint) {
reserve(v, uint::next_power_of_two(n));
}
/// Returns the number of elements the vector can hold without reallocating
#[inline(always)]
pure fn capacity<T>(&&v: ~[const T]) -> uint {
unsafe {
let repr: **unsafe::vec_repr = ::unsafe::reinterpret_cast(addr_of(v));
(**repr).alloc / sys::size_of::<T>()
}
}
/// Returns the length of a vector
#[inline(always)]
pure fn len<T>(&&v: &[const T]) -> uint {
as_const_buf(v, |_p, len| len)
}
/**
* Creates and initializes an immutable vector.
*
* Creates an immutable vector of size `n_elts` and initializes the elements
* to the value returned by the function `op`.
*/
pure fn from_fn<T>(n_elts: uint, op: init_op<T>) -> ~[T] {
let mut v = ~[];
unchecked{reserve(v, n_elts);}
let mut i: uint = 0u;
while i < n_elts unsafe { unsafe::set(v, i, op(i)); i += 1u; }
unsafe { unsafe::set_len(v, n_elts); }
return v;
}
/**
* Creates and initializes an immutable vector.
*
* Creates an immutable vector of size `n_elts` and initializes the elements
* to the value `t`.
*/
pure fn from_elem<T: copy>(n_elts: uint, t: T) -> ~[T] {
let mut v = ~[];
unchecked{reserve(v, n_elts)}
let mut i: uint = 0u;
unsafe { // because unsafe::set is unsafe
while i < n_elts { unsafe::set(v, i, t); i += 1u; }
unsafe { unsafe::set_len(v, n_elts); }
}
return v;
}
/**
* Builds a vector by calling a provided function with an argument
* function that pushes an element to the back of a vector.
* This version takes an initial size for the vector.
*
* # Arguments
*
* * size - An initial size of the vector to reserve
* * builder - A function that will construct the vector. It recieves
* as an argument a function that will push an element
* onto the vector being constructed.
*/
#[inline(always)]
pure fn build_sized<A>(size: uint, builder: fn(push: pure fn(+A))) -> ~[A] {
let mut vec = ~[];
unsafe {
reserve(vec, size);
// This is an awful hack to be able to make the push function
// pure. Is there a better way?
::unsafe::reinterpret_cast::
<fn(push: pure fn(+A)), fn(push: fn(+A))>
(builder)(|+x| push(vec, x));
}
return vec;
}
/**
* Builds a vector by calling a provided function with an argument
* function that pushes an element to the back of a vector.
*
* # Arguments
*
* * builder - A function that will construct the vector. It recieves
* as an argument a function that will push an element
* onto the vector being constructed.
*/
#[inline(always)]
pure fn build<A>(builder: fn(push: pure fn(+A))) -> ~[A] {
build_sized(4, builder)
}
/// Produces a mut vector from an immutable vector.
pure fn to_mut<T>(+v: ~[T]) -> ~[mut T] {
unsafe { ::unsafe::transmute(v) }
}
/// Produces an immutable vector from a mut vector.
pure fn from_mut<T>(+v: ~[mut T]) -> ~[T] {
unsafe { ::unsafe::transmute(v) }
}
// Accessors
/// Returns the first element of a vector
pure fn head<T: copy>(v: &[const T]) -> T { v[0] }
/// Returns a vector containing all but the first element of a slice
pure fn tail<T: copy>(v: &[const T]) -> ~[T] {
return slice(v, 1u, len(v));
}
/**
* Returns a vector containing all but the first `n` \
* elements of a slice
*/
pure fn tailn<T: copy>(v: &[const T], n: uint) -> ~[T] {
slice(v, n, len(v))
}
/// Returns a vector containing all but the last element of a slice
pure fn init<T: copy>(v: &[const T]) -> ~[T] {
assert len(v) != 0u;
slice(v, 0u, len(v) - 1u)
}
/// Returns the last element of the slice `v`, failing if the slice is empty.
pure fn last<T: copy>(v: &[const T]) -> T {
if len(v) == 0u { fail ~"last_unsafe: empty vector" }
v[len(v) - 1u]
}
/**
* Returns `some(x)` where `x` is the last element of the slice `v`,
* or `none` if the vector is empty.
*/
pure fn last_opt<T: copy>(v: &[const T]) -> option<T> {
if len(v) == 0u { return none; }
some(v[len(v) - 1u])
}
/// Returns a copy of the elements from [`start`..`end`) from `v`.
pure fn slice<T: copy>(v: &[const T], start: uint, end: uint) -> ~[T] {
assert (start <= end);
assert (end <= len(v));
let mut result = ~[];
unchecked {
for uint::range(start, end) |i| { vec::push(result, v[i]) }
}
return result;
}
/// Return a slice that points into another slice.
pure fn view<T>(v: &[T], start: uint, end: uint) -> &[T] {
assert (start <= end);
assert (end <= len(v));
do as_buf(v) |p, _len| {
unsafe {
::unsafe::reinterpret_cast(
(ptr::offset(p, start), (end - start) * sys::size_of::<T>()))
}
}
}
/// Return a slice that points into another slice.
pure fn mut_view<T>(v: &[mut T], start: uint, end: uint) -> &[mut T] {
assert (start <= end);
assert (end <= len(v));
do as_buf(v) |p, _len| {
unsafe {
::unsafe::reinterpret_cast(
(ptr::offset(p, start), (end - start) * sys::size_of::<T>()))
}
}
}
/// Return a slice that points into another slice.
pure fn const_view<T>(v: &[const T], start: uint, end: uint) -> &[const T] {
assert (start <= end);
assert (end <= len(v));
do as_buf(v) |p, _len| {
unsafe {
::unsafe::reinterpret_cast(
(ptr::offset(p, start), (end - start) * sys::size_of::<T>()))
}
}
}
/// Split the vector `v` by applying each element against the predicate `f`.
fn split<T: copy>(v: &[T], f: fn(T) -> bool) -> ~[~[T]] {
let ln = len(v);
if (ln == 0u) { return ~[] }
let mut start = 0u;
let mut result = ~[];
while start < ln {
alt position_between(v, start, ln, f) {
none { break }
some(i) {
push(result, slice(v, start, i));
start = i + 1u;
}
}
}
push(result, slice(v, start, ln));
result
}
/**
* Split the vector `v` by applying each element against the predicate `f` up
* to `n` times.
*/
fn splitn<T: copy>(v: &[T], n: uint, f: fn(T) -> bool) -> ~[~[T]] {
let ln = len(v);
if (ln == 0u) { return ~[] }
let mut start = 0u;
let mut count = n;
let mut result = ~[];
while start < ln && count > 0u {
alt position_between(v, start, ln, f) {
none { break }
some(i) {
push(result, slice(v, start, i));
// Make sure to skip the separator.
start = i + 1u;
count -= 1u;
}
}
}
push(result, slice(v, start, ln));
result
}
/**
* Reverse split the vector `v` by applying each element against the predicate
* `f`.
*/
fn rsplit<T: copy>(v: &[T], f: fn(T) -> bool) -> ~[~[T]] {
let ln = len(v);
if (ln == 0u) { return ~[] }
let mut end = ln;
let mut result = ~[];
while end > 0u {
alt rposition_between(v, 0u, end, f) {
none { break }
some(i) {
push(result, slice(v, i + 1u, end));
end = i;
}
}
}
push(result, slice(v, 0u, end));
reversed(result)
}
/**
* Reverse split the vector `v` by applying each element against the predicate
* `f` up to `n times.
*/
fn rsplitn<T: copy>(v: &[T], n: uint, f: fn(T) -> bool) -> ~[~[T]] {
let ln = len(v);
if (ln == 0u) { return ~[] }
let mut end = ln;
let mut count = n;
let mut result = ~[];
while end > 0u && count > 0u {
alt rposition_between(v, 0u, end, f) {
none { break }
some(i) {
push(result, slice(v, i + 1u, end));
// Make sure to skip the separator.
end = i;
count -= 1u;
}
}
}
push(result, slice(v, 0u, end));
reversed(result)
}
// Mutators
/// Removes the first element from a vector and return it
fn shift<T>(&v: ~[T]) -> T {
let ln = len::<T>(v);
assert (ln > 0);
let mut vv = ~[];
v <-> vv;
unsafe {
let mut rr;
{
let vv = unsafe::to_ptr(vv);
rr <- *vv;
for uint::range(1, ln) |i| {
let r <- *ptr::offset(vv, i);
push(v, r);
}
}
unsafe::set_len(vv, 0);
rr
}
}
/// Prepend an element to the vector
fn unshift<T>(&v: ~[T], +x: T) {
let mut vv = ~[x];
v <-> vv;
while len(vv) > 0 {
push(v, shift(vv));
}
}
fn consume<T>(+v: ~[T], f: fn(uint, +T)) unsafe {
do as_buf(v) |p, ln| {
for uint::range(0, ln) |i| {
let x <- *ptr::offset(p, i);
f(i, x);
}
}
unsafe::set_len(v, 0);
}
/// Remove the last element from a vector and return it
fn pop<T>(&v: ~[const T]) -> T {
let ln = len(v);
assert ln > 0u;
let valptr = ptr::mut_addr_of(v[ln - 1u]);
unsafe {
let val <- *valptr;
unsafe::set_len(v, ln - 1u);
val
}
}
/// Append an element to a vector
#[inline(always)]
fn push<T>(&v: ~[const T], +initval: T) {
unsafe {
let repr: **unsafe::vec_repr = ::unsafe::reinterpret_cast(addr_of(v));
let fill = (**repr).fill;
if (**repr).alloc > fill {
push_fast(v, initval);
}
else {
push_slow(v, initval);
}
}
}
// This doesn't bother to make sure we have space.
#[inline(always)] // really pretty please
unsafe fn push_fast<T>(&v: ~[const T], +initval: T) {
let repr: **unsafe::vec_repr = ::unsafe::reinterpret_cast(addr_of(v));
let fill = (**repr).fill;
(**repr).fill += sys::size_of::<T>();
let p = ptr::addr_of((**repr).data);
let p = ptr::offset(p, fill) as *mut T;
rusti::move_val_init(*p, initval);
}
#[inline(never)]
fn push_slow<T>(&v: ~[const T], +initval: T) {
reserve_at_least(v, v.len() + 1u);
unsafe { push_fast(v, initval) }
}
#[inline(always)]
fn push_all<T: copy>(&v: ~[const T], rhs: &[const T]) {
reserve(v, v.len() + rhs.len());
for uint::range(0u, rhs.len()) |i| {
push(v, unsafe { unsafe::get(rhs, i) })
}
}
#[inline(always)]
fn push_all_move<T>(&v: ~[const T], -rhs: ~[const T]) {
reserve(v, v.len() + rhs.len());
unsafe {
do as_buf(rhs) |p, len| {
for uint::range(0, len) |i| {
let x <- *ptr::offset(p, i);
push(v, x);
}
}
unsafe::set_len(rhs, 0);
}
}
// Appending
#[inline(always)]
pure fn append<T: copy>(+lhs: ~[T], rhs: &[const T]) -> ~[T] {
let mut v <- lhs;
unchecked {
push_all(v, rhs);
}
return v;
}
#[inline(always)]
pure fn append_one<T>(+lhs: ~[T], +x: T) -> ~[T] {
let mut v <- lhs;
unchecked { push(v, x); }
v
}
#[inline(always)]
pure fn append_mut<T: copy>(lhs: &[mut T], rhs: &[const T]) -> ~[mut T] {
let mut v = ~[mut];
let mut i = 0u;
while i < lhs.len() {
unsafe { // This is impure, but it appears pure to the caller.
push(v, lhs[i]);
}
i += 1u;
}
i = 0u;
while i < rhs.len() {
unsafe { // This is impure, but it appears pure to the caller.
push(v, rhs[i]);
}
i += 1u;
}
return v;
}
/**
* Expands a vector in place, initializing the new elements to a given value
*
* # Arguments
*
* * v - The vector to grow
* * n - The number of elements to add
* * initval - The value for the new elements
*/
fn grow<T: copy>(&v: ~[const T], n: uint, initval: T) {
reserve_at_least(v, len(v) + n);
let mut i: uint = 0u;
while i < n { push(v, initval); i += 1u; }
}
/**
* Expands a vector in place, initializing the new elements to the result of
* a function
*
* Function `init_op` is called `n` times with the values [0..`n`)
*
* # Arguments
*
* * v - The vector to grow
* * n - The number of elements to add
* * init_op - A function to call to retreive each appended element's
* value
*/
fn grow_fn<T>(&v: ~[const T], n: uint, op: init_op<T>) {
reserve_at_least(v, len(v) + n);
let mut i: uint = 0u;
while i < n { push(v, op(i)); i += 1u; }
}
/**
* Sets the value of a vector element at a given index, growing the vector as
* needed
*
* Sets the element at position `index` to `val`. If `index` is past the end
* of the vector, expands the vector by replicating `initval` to fill the
* intervening space.
*/
fn grow_set<T: copy>(&v: ~[mut T], index: uint, initval: T, val: T) {
if index >= len(v) { grow(v, index - len(v) + 1u, initval); }
v[index] = val;
}
// Functional utilities
/// Apply a function to each element of a vector and return the results
pure fn map<T, U>(v: &[T], f: fn(T) -> U) -> ~[U] {
let mut result = ~[];
unchecked{reserve(result, len(v));}
for each(v) |elem| { unsafe { push(result, f(elem)); } }
return result;
}
fn map_consume<T, U>(+v: ~[T], f: fn(+T) -> U) -> ~[U] {
let mut result = ~[];
do consume(v) |_i, x| {
vec::push(result, f(x));
}
result
}
/// Apply a function to each element of a vector and return the results
pure fn mapi<T, U>(v: &[T], f: fn(uint, T) -> U) -> ~[U] {
let mut result = ~[];
unchecked{reserve(result, len(v));}
for eachi(v) |i, elem| { unsafe { push(result, f(i, elem)); } }
return result;
}
/**
* Apply a function to each element of a vector and return a concatenation
* of each result vector
*/
pure fn flat_map<T, U>(v: &[T], f: fn(T) -> ~[U]) -> ~[U] {
let mut result = ~[];
for each(v) |elem| { unchecked{ push_all_move(result, f(elem)); } }
return result;
}
/// Apply a function to each pair of elements and return the results
pure fn map2<T: copy, U: copy, V>(v0: &[T], v1: &[U],
f: fn(T, U) -> V) -> ~[V] {
let v0_len = len(v0);
if v0_len != len(v1) { fail; }
let mut u: ~[V] = ~[];
let mut i = 0u;
while i < v0_len {
unsafe { push(u, f(copy v0[i], copy v1[i])) };
i += 1u;
}
return u;
}
/**
* Apply a function to each element of a vector and return the results
*
* If function `f` returns `none` then that element is excluded from
* the resulting vector.
*/
pure fn filter_map<T, U: copy>(v: &[T], f: fn(T) -> option<U>)
-> ~[U] {
let mut result = ~[];
for each(v) |elem| {
alt f(elem) {
none {/* no-op */ }
some(result_elem) { unsafe { push(result, result_elem); } }
}
}
return result;
}
/**
* Construct a new vector from the elements of a vector for which some
* predicate holds.
*
* Apply function `f` to each element of `v` and return a vector containing
* only those elements for which `f` returned true.
*/
pure fn filter<T: copy>(v: &[T], f: fn(T) -> bool) -> ~[T] {
let mut result = ~[];
for each(v) |elem| {
if f(elem) { unsafe { push(result, elem); } }
}
return result;
}
/**
* Concatenate a vector of vectors.
*
* Flattens a vector of vectors of T into a single vector of T.
*/
pure fn concat<T: copy>(v: &[~[T]]) -> ~[T] {
let mut r = ~[];
for each(v) |inner| { unsafe { push_all(r, inner); } }
return r;
}
/// Concatenate a vector of vectors, placing a given separator between each
pure fn connect<T: copy>(v: &[~[T]], sep: T) -> ~[T] {
let mut r: ~[T] = ~[];
let mut first = true;
for each(v) |inner| {
if first { first = false; } else { unsafe { push(r, sep); } }
unchecked { push_all(r, inner) };
}
return r;
}
/// Reduce a vector from left to right
pure fn foldl<T: copy, U>(z: T, v: &[U], p: fn(T, U) -> T) -> T {
let mut accum = z;
do iter(v) |elt| {
accum = p(accum, elt);
}
return accum;
}
/// Reduce a vector from right to left
pure fn foldr<T, U: copy>(v: &[T], z: U, p: fn(T, U) -> U) -> U {
let mut accum = z;
do riter(v) |elt| {
accum = p(elt, accum);
}
return accum;
}
/**
* Return true if a predicate matches any elements
*
* If the vector contains no elements then false is returned.
*/
pure fn any<T>(v: &[T], f: fn(T) -> bool) -> bool {
for each(v) |elem| { if f(elem) { return true; } }
return false;
}
/**
* Return true if a predicate matches any elements in both vectors.
*
* If the vectors contains no elements then false is returned.
*/
pure fn any2<T, U>(v0: &[T], v1: &[U],
f: fn(T, U) -> bool) -> bool {
let v0_len = len(v0);
let v1_len = len(v1);
let mut i = 0u;
while i < v0_len && i < v1_len {
if f(v0[i], v1[i]) { return true; };
i += 1u;
}
return false;
}
/**
* Return true if a predicate matches all elements
*
* If the vector contains no elements then true is returned.
*/
pure fn all<T>(v: &[T], f: fn(T) -> bool) -> bool {
for each(v) |elem| { if !f(elem) { return false; } }
return true;
}
/**
* Return true if a predicate matches all elements
*
* If the vector contains no elements then true is returned.
*/
pure fn alli<T>(v: &[T], f: fn(uint, T) -> bool) -> bool {
for eachi(v) |i, elem| { if !f(i, elem) { return false; } }
return true;
}
/**
* Return true if a predicate matches all elements in both vectors.
*
* If the vectors are not the same size then false is returned.
*/
pure fn all2<T, U>(v0: &[T], v1: &[U],
f: fn(T, U) -> bool) -> bool {
let v0_len = len(v0);
if v0_len != len(v1) { return false; }
let mut i = 0u;
while i < v0_len { if !f(v0[i], v1[i]) { return false; }; i += 1u; }
return true;
}
/// Return true if a vector contains an element with the given value
pure fn contains<T>(v: &[T], x: T) -> bool {
for each(v) |elt| { if x == elt { return true; } }
return false;
}
/// Returns the number of elements that are equal to a given value
pure fn count<T>(v: &[T], x: T) -> uint {
let mut cnt = 0u;
for each(v) |elt| { if x == elt { cnt += 1u; } }
return cnt;
}
/**
* Search for the first element that matches a given predicate
*
* Apply function `f` to each element of `v`, starting from the first.
* When function `f` returns true then an option containing the element
* is returned. If `f` matches no elements then none is returned.
*/
pure fn find<T: copy>(v: &[T], f: fn(T) -> bool) -> option<T> {
find_between(v, 0u, len(v), f)
}
/**
* Search for the first element that matches a given predicate within a range
*
* Apply function `f` to each element of `v` within the range
* [`start`, `end`). When function `f` returns true then an option containing
* the element is returned. If `f` matches no elements then none is returned.
*/
pure fn find_between<T: copy>(v: &[T], start: uint, end: uint,
f: fn(T) -> bool) -> option<T> {
option::map(position_between(v, start, end, f), |i| v[i])
}
/**
* Search for the last element that matches a given predicate
*
* Apply function `f` to each element of `v` in reverse order. When function
* `f` returns true then an option containing the element is returned. If `f`
* matches no elements then none is returned.
*/
pure fn rfind<T: copy>(v: &[T], f: fn(T) -> bool) -> option<T> {
rfind_between(v, 0u, len(v), f)
}
/**
* Search for the last element that matches a given predicate within a range
*
* Apply function `f` to each element of `v` in reverse order within the range
* [`start`, `end`). When function `f` returns true then an option containing
* the element is returned. If `f` matches no elements then none is returned.
*/
pure fn rfind_between<T: copy>(v: &[T], start: uint, end: uint,
f: fn(T) -> bool) -> option<T> {
option::map(rposition_between(v, start, end, f), |i| v[i])
}
/// Find the first index containing a matching value
pure fn position_elem<T>(v: &[T], x: T) -> option<uint> {
position(v, |y| x == y)
}
/**
* Find the first index matching some predicate
*
* Apply function `f` to each element of `v`. When function `f` returns true
* then an option containing the index is returned. If `f` matches no elements
* then none is returned.
*/
pure fn position<T>(v: &[T], f: fn(T) -> bool) -> option<uint> {
position_between(v, 0u, len(v), f)
}
/**
* Find the first index matching some predicate within a range
*
* Apply function `f` to each element of `v` between the range
* [`start`, `end`). When function `f` returns true then an option containing
* the index is returned. If `f` matches no elements then none is returned.
*/
pure fn position_between<T>(v: &[T], start: uint, end: uint,
f: fn(T) -> bool) -> option<uint> {
assert start <= end;
assert end <= len(v);
let mut i = start;
while i < end { if f(v[i]) { return some::<uint>(i); } i += 1u; }
return none;
}
/// Find the last index containing a matching value
pure fn rposition_elem<T>(v: &[T], x: T) -> option<uint> {
rposition(v, |y| x == y)
}
/**
* Find the last index matching some predicate
*
* Apply function `f` to each element of `v` in reverse order. When function
* `f` returns true then an option containing the index is returned. If `f`
* matches no elements then none is returned.
*/
pure fn rposition<T>(v: &[T], f: fn(T) -> bool) -> option<uint> {
rposition_between(v, 0u, len(v), f)
}
/**
* Find the last index matching some predicate within a range
*
* Apply function `f` to each element of `v` in reverse order between the
* range [`start`, `end`). When function `f` returns true then an option
* containing the index is returned. If `f` matches no elements then none is
* returned.
*/
pure fn rposition_between<T>(v: &[T], start: uint, end: uint,
f: fn(T) -> bool) -> option<uint> {
assert start <= end;
assert end <= len(v);
let mut i = end;
while i > start {
if f(v[i - 1u]) { return some::<uint>(i - 1u); }
i -= 1u;
}
return none;
}
// FIXME: if issue #586 gets implemented, could have a postcondition
// saying the two result lists have the same length -- or, could
// return a nominal record with a constraint saying that, instead of
// returning a tuple (contingent on issue #869)
/**
* Convert a vector of pairs into a pair of vectors
*
* Returns a tuple containing two vectors where the i-th element of the first
* vector contains the first element of the i-th tuple of the input vector,
* and the i-th element of the second vector contains the second element
* of the i-th tuple of the input vector.
*/
pure fn unzip<T: copy, U: copy>(v: &[(T, U)]) -> (~[T], ~[U]) {
let mut as = ~[], bs = ~[];
for each(v) |p| {
let (a, b) = p;
unchecked {
vec::push(as, a);
vec::push(bs, b);
}
}
return (as, bs);
}
/**
* Convert two vectors to a vector of pairs
*
* Returns a vector of tuples, where the i-th tuple contains contains the
* i-th elements from each of the input vectors.
*/
pure fn zip<T: copy, U: copy>(v: &[const T], u: &[const U]) -> ~[(T, U)] {
let mut zipped = ~[];
let sz = len(v);
let mut i = 0u;
assert sz == len(u);
while i < sz unchecked { vec::push(zipped, (v[i], u[i])); i += 1u; }
return zipped;
}
/**
* Swaps two elements in a vector
*
* # Arguments
*
* * v The input vector
* * a - The index of the first element
* * b - The index of the second element
*/
fn swap<T>(&&v: ~[mut T], a: uint, b: uint) {
v[a] <-> v[b];
}
/// Reverse the order of elements in a vector, in place
fn reverse<T>(v: ~[mut T]) {
let mut i: uint = 0u;
let ln = len::<T>(v);
while i < ln / 2u { v[i] <-> v[ln - i - 1u]; i += 1u; }
}
/// Returns a vector with the order of elements reversed
pure fn reversed<T: copy>(v: &[const T]) -> ~[T] {
let mut rs: ~[T] = ~[];
let mut i = len::<T>(v);
if i == 0u { return rs; } else { i -= 1u; }
unchecked {
while i != 0u { vec::push(rs, v[i]); i -= 1u; }
vec::push(rs, v[0]);
}
return rs;
}
/**
* Iterates over a slice
*
* Iterates over slice `v` and, for each element, calls function `f` with the
* element's value.
*/
#[inline(always)]
pure fn iter<T>(v: &[T], f: fn(T)) {
iter_between(v, 0u, vec::len(v), f)
}
/*
Function: iter_between
Iterates over a slice
Iterates over slice `v` and, for each element, calls function `f` with the
element's value.
*/
#[inline(always)]
pure fn iter_between<T>(v: &[T], start: uint, end: uint, f: fn(T)) {
do as_buf(v) |base_ptr, len| {
assert start <= end;
assert end <= len;
unsafe {
let mut n = end;
let mut p = ptr::offset(base_ptr, start);
while n > start {
f(*p);
p = ptr::offset(p, 1u);
n -= 1u;
}
}
}
}
/**
* Iterates over a vector, with option to break
*
* Return true to continue, false to break.
*/
#[inline(always)]
pure fn each<T>(v: &[T], f: fn(T) -> bool) {
do vec::as_buf(v) |p, n| {
let mut n = n;
let mut p = p;
while n > 0u {
unsafe {
if !f(*p) { break; }
p = ptr::offset(p, 1u);
}
n -= 1u;
}
}
}
/**
* Iterates over a vector's elements and indices
*
* Return true to continue, false to break.
*/
#[inline(always)]
pure fn eachi<T>(v: &[T], f: fn(uint, T) -> bool) {
do vec::as_buf(v) |p, n| {
let mut i = 0u;
let mut p = p;
while i < n {
unsafe {
if !f(i, *p) { break; }
p = ptr::offset(p, 1u);
}
i += 1u;
}
}
}
/**
* Iterates over a vector's elements in reverse
*
* Return true to continue, false to break.
*/
#[inline(always)]
pure fn reach<T>(v: &[T], blk: fn(T) -> bool) {
do vec::as_buf(v) |p, n| {
let mut i = 1;
while i <= n {
unsafe {
if !blk(*ptr::offset(p, n-i)) { break; }
}
i += 1;
}
}
}
/**
* Iterates over a vector's elements and indices in reverse
*
* Return true to continue, false to break.
*/
#[inline(always)]
pure fn reachi<T>(v: &[T], blk: fn(uint, T) -> bool) {
do vec::as_buf(v) |p, n| {
let mut i = 1;
while i <= n {
unsafe {
if !blk(n-i, *ptr::offset(p, n-i)) { break; }
}
i += 1;
}
}
}
/**
* Iterates over two vectors simultaneously
*
* # Failure
*
* Both vectors must have the same length
*/
#[inline]
fn iter2<U, T>(v1: &[U], v2: &[T], f: fn(U, T)) {
assert len(v1) == len(v2);
for uint::range(0u, len(v1)) |i| {
f(v1[i], v2[i])
}
}
/**
* Iterates over a vector's elements and indexes
*
* Iterates over vector `v` and, for each element, calls function `f` with the
* element's value and index.
*/
#[inline(always)]
pure fn iteri<T>(v: &[T], f: fn(uint, T)) {
let mut i = 0u;
let l = len(v);
while i < l { f(i, v[i]); i += 1u; }
}
/**
* Iterates over a vector in reverse
*
* Iterates over vector `v` and, for each element, calls function `f` with the
* element's value.
*/
pure fn riter<T>(v: &[T], f: fn(T)) {
riteri(v, |_i, v| f(v))
}
/**
* Iterates over a vector's elements and indexes in reverse
*
* Iterates over vector `v` and, for each element, calls function `f` with the
* element's value and index.
*/
pure fn riteri<T>(v: &[T], f: fn(uint, T)) {
let mut i = len(v);
while 0u < i {
i -= 1u;
f(i, v[i]);
};
}
/**
* Iterate over all permutations of vector `v`.
*
* Permutations are produced in lexicographic order with respect to the order
* of elements in `v` (so if `v` is sorted then the permutations are
* lexicographically sorted).
*
* The total number of permutations produced is `len(v)!`. If `v` contains
* repeated elements, then some permutations are repeated.
*/
pure fn permute<T: copy>(v: &[T], put: fn(~[T])) {
let ln = len(v);
if ln == 0u {
put(~[]);
} else {
let mut i = 0u;
while i < ln {
let elt = v[i];
let mut rest = slice(v, 0u, i);
unchecked {
push_all(rest, view(v, i+1u, ln));
permute(rest, |permutation| {
put(append(~[elt], permutation))
})
}
i += 1u;
}
}
}
pure fn windowed<TT: copy>(nn: uint, xx: &[TT]) -> ~[~[TT]] {
let mut ww = ~[];
assert 1u <= nn;
vec::iteri (xx, |ii, _x| {
let len = vec::len(xx);
if ii+nn <= len unchecked {
vec::push(ww, vec::slice(xx, ii, ii+nn));
}
});
return ww;
}
/**
* Work with the buffer of a vector.
*
* Allows for unsafe manipulation of vector contents, which is useful for
* foreign interop.
*/
#[inline(always)]
pure fn as_buf<T,U>(s: &[const T],
f: fn(*T, uint) -> U) -> U {
unsafe {
let v : *(*T,uint) = ::unsafe::reinterpret_cast(ptr::addr_of(s));
let (buf,len) = *v;
f(buf, len / sys::size_of::<T>())
}
}
/// Similar to `as_buf` but passing a `*const T`
#[inline(always)]
pure fn as_const_buf<T,U>(s: &[const T],
f: fn(*const T, uint) -> U) -> U {
do as_buf(s) |p, len| {
unsafe {
let pp : *const T = ::unsafe::reinterpret_cast(p);
f(pp, len)
}
}
}
/// Similar to `as_buf` but passing a `*mut T`
#[inline(always)]
pure fn as_mut_buf<T,U>(s: &[mut T],
f: fn(*mut T, uint) -> U) -> U {
do as_buf(s) |p, len| {
unsafe {
let pp : *mut T = ::unsafe::reinterpret_cast(p);
f(pp, len)
}
}
}
trait vec_concat<T> {
pure fn +(rhs: &[const T]) -> self;
}
impl extensions<T: copy> of vec_concat<T> for ~[T] {
#[inline(always)]
pure fn +(rhs: &[const T]) -> ~[T] {
append(self, rhs)
}
}
#[cfg(notest)]
impl extensions<T: copy> of add<&[const T],~[T]> for ~[T] {
#[inline(always)]
pure fn add(rhs: &[const T]) -> ~[T] {
append(self, rhs)
}
}
impl extensions<T: copy> of vec_concat<T> for ~[mut T] {
#[inline(always)]
pure fn +(rhs: &[const T]) -> ~[mut T] {
append_mut(self, rhs)
}
}
impl extensions<T: copy> of add<&[const T],~[mut T]> for ~[mut T] {
#[inline(always)]
pure fn add(rhs: &[const T]) -> ~[mut T] {
append_mut(self, rhs)
}
}
trait const_vector {
pure fn is_empty() -> bool;
pure fn is_not_empty() -> bool;
pure fn len() -> uint;
}
/// Extension methods for vectors
impl extensions/&<T> of const_vector for &[const T] {
/// Returns true if a vector contains no elements
#[inline]
pure fn is_empty() -> bool { is_empty(self) }
/// Returns true if a vector contains some elements
#[inline]
pure fn is_not_empty() -> bool { is_not_empty(self) }
/// Returns the length of a vector
#[inline]
pure fn len() -> uint { len(self) }
}
trait copyable_vector<T> {
pure fn head() -> T;
pure fn init() -> ~[T];
pure fn last() -> T;
pure fn slice(start: uint, end: uint) -> ~[T];
pure fn tail() -> ~[T];
}
/// Extension methods for vectors
impl extensions/&<T: copy> of copyable_vector<T> for &[const T] {
/// Returns the first element of a vector
#[inline]
pure fn head() -> T { head(self) }
/// Returns all but the last elemnt of a vector
#[inline]
pure fn init() -> ~[T] { init(self) }
/// Returns the last element of a `v`, failing if the vector is empty.
#[inline]
pure fn last() -> T { last(self) }
/// Returns a copy of the elements from [`start`..`end`) from `v`.
#[inline]
pure fn slice(start: uint, end: uint) -> ~[T] { slice(self, start, end) }
/// Returns all but the first element of a vector
#[inline]
pure fn tail() -> ~[T] { tail(self) }
}
trait immutable_vector<T> {
pure fn foldr<U: copy>(z: U, p: fn(T, U) -> U) -> U;
pure fn iter(f: fn(T));
pure fn iteri(f: fn(uint, T));
pure fn position(f: fn(T) -> bool) -> option<uint>;
pure fn position_elem(x: T) -> option<uint>;
pure fn riter(f: fn(T));
pure fn riteri(f: fn(uint, T));
pure fn rposition(f: fn(T) -> bool) -> option<uint>;
pure fn rposition_elem(x: T) -> option<uint>;
pure fn map<U>(f: fn(T) -> U) -> ~[U];
pure fn mapi<U>(f: fn(uint, T) -> U) -> ~[U];
fn map_r<U>(f: fn(x: &T) -> U) -> ~[U];
pure fn alli(f: fn(uint, T) -> bool) -> bool;
pure fn flat_map<U>(f: fn(T) -> ~[U]) -> ~[U];
pure fn filter_map<U: copy>(f: fn(T) -> option<U>) -> ~[U];
}
/// Extension methods for vectors
impl extensions/&<T> of immutable_vector<T> for &[T] {
/// Reduce a vector from right to left
#[inline]
pure fn foldr<U: copy>(z: U, p: fn(T, U) -> U) -> U { foldr(self, z, p) }
/**
* Iterates over a vector
*
* Iterates over vector `v` and, for each element, calls function `f` with
* the element's value.
*/
#[inline]
pure fn iter(f: fn(T)) { iter(self, f) }
/**
* Iterates over a vector's elements and indexes
*
* Iterates over vector `v` and, for each element, calls function `f` with
* the element's value and index.
*/
#[inline]
pure fn iteri(f: fn(uint, T)) { iteri(self, f) }
/**
* Find the first index matching some predicate
*
* Apply function `f` to each element of `v`. When function `f` returns
* true then an option containing the index is returned. If `f` matches no
* elements then none is returned.
*/
#[inline]
pure fn position(f: fn(T) -> bool) -> option<uint> { position(self, f) }
/// Find the first index containing a matching value
#[inline]
pure fn position_elem(x: T) -> option<uint> { position_elem(self, x) }
/**
* Iterates over a vector in reverse
*
* Iterates over vector `v` and, for each element, calls function `f` with
* the element's value.
*/
#[inline]
pure fn riter(f: fn(T)) { riter(self, f) }
/**
* Iterates over a vector's elements and indexes in reverse
*
* Iterates over vector `v` and, for each element, calls function `f` with
* the element's value and index.
*/
#[inline]
pure fn riteri(f: fn(uint, T)) { riteri(self, f) }
/**
* Find the last index matching some predicate
*
* Apply function `f` to each element of `v` in reverse order. When
* function `f` returns true then an option containing the index is
* returned. If `f` matches no elements then none is returned.
*/
#[inline]
pure fn rposition(f: fn(T) -> bool) -> option<uint> { rposition(self, f) }
/// Find the last index containing a matching value
#[inline]
pure fn rposition_elem(x: T) -> option<uint> { rposition_elem(self, x) }
/// Apply a function to each element of a vector and return the results
#[inline]
pure fn map<U>(f: fn(T) -> U) -> ~[U] { map(self, f) }
/**
* Apply a function to the index and value of each element in the vector
* and return the results
*/
pure fn mapi<U>(f: fn(uint, T) -> U) -> ~[U] {
mapi(self, f)
}
#[inline]
fn map_r<U>(f: fn(x: &T) -> U) -> ~[U] {
let mut r = ~[];
let mut i = 0;
while i < self.len() {
push(r, f(&self[i]));
i += 1;
}
r
}
/**
* Returns true if the function returns true for all elements.
*
* If the vector is empty, true is returned.
*/
pure fn alli(f: fn(uint, T) -> bool) -> bool {
alli(self, f)
}
/**
* Apply a function to each element of a vector and return a concatenation
* of each result vector
*/
#[inline]
pure fn flat_map<U>(f: fn(T) -> ~[U]) -> ~[U] { flat_map(self, f) }
/**
* Apply a function to each element of a vector and return the results
*
* If function `f` returns `none` then that element is excluded from
* the resulting vector.
*/
#[inline]
pure fn filter_map<U: copy>(f: fn(T) -> option<U>) -> ~[U] {
filter_map(self, f)
}
}
trait immutable_copyable_vector<T> {
pure fn filter(f: fn(T) -> bool) -> ~[T];
pure fn find(f: fn(T) -> bool) -> option<T>;
pure fn rfind(f: fn(T) -> bool) -> option<T>;
}
/// Extension methods for vectors
impl extensions/&<T: copy> of immutable_copyable_vector<T> for &[T] {
/**
* Construct a new vector from the elements of a vector for which some
* predicate holds.
*
* Apply function `f` to each element of `v` and return a vector
* containing only those elements for which `f` returned true.
*/
#[inline]
pure fn filter(f: fn(T) -> bool) -> ~[T] { filter(self, f) }
/**
* Search for the first element that matches a given predicate
*
* Apply function `f` to each element of `v`, starting from the first.
* When function `f` returns true then an option containing the element
* is returned. If `f` matches no elements then none is returned.
*/
#[inline]
pure fn find(f: fn(T) -> bool) -> option<T> { find(self, f) }
/**
* Search for the last element that matches a given predicate
*
* Apply function `f` to each element of `v` in reverse order. When
* function `f` returns true then an option containing the element is
* returned. If `f` matches no elements then none is returned.
*/
#[inline]
pure fn rfind(f: fn(T) -> bool) -> option<T> { rfind(self, f) }
}
/// Unsafe operations
mod unsafe {
// FIXME: This should have crate visibility (#1893 blocks that)
/// The internal representation of a vector
type vec_repr = {
box_header: (uint, uint, uint, uint),
mut fill: uint,
mut alloc: uint,
data: u8
};
type slice_repr = {
mut data: *u8,
mut len: uint
};
/**
* Constructs a vector from an unsafe pointer to a buffer
*
* # Arguments
*
* * ptr - An unsafe pointer to a buffer of `T`
* * elts - The number of elements in the buffer
*/
#[inline(always)]
unsafe fn from_buf<T>(ptr: *T, elts: uint) -> ~[T] {
return ::unsafe::reinterpret_cast(
rustrt::vec_from_buf_shared(sys::get_type_desc::<T>(),
ptr as *(),
elts as size_t));
}
/**
* Sets the length of a vector
*
* This will explicitly set the size of the vector, without actually
* modifing its buffers, so it is up to the caller to ensure that
* the vector is actually the specified size.
*/
#[inline(always)]
unsafe fn set_len<T>(&&v: ~[const T], new_len: uint) {
let repr: **vec_repr = ::unsafe::reinterpret_cast(addr_of(v));
(**repr).fill = new_len * sys::size_of::<T>();
}
/**
* Returns an unsafe pointer to the vector's buffer
*
* The caller must ensure that the vector outlives the pointer this
* function returns, or else it will end up pointing to garbage.
*
* Modifying the vector may cause its buffer to be reallocated, which
* would also make any pointers to it invalid.
*/
#[inline(always)]
unsafe fn to_ptr<T>(v: ~[const T]) -> *T {
let repr: **vec_repr = ::unsafe::reinterpret_cast(addr_of(v));
return ::unsafe::reinterpret_cast(addr_of((**repr).data));
}
#[inline(always)]
unsafe fn to_ptr_slice<T>(v: &[const T]) -> *T {
let repr: **slice_repr = ::unsafe::reinterpret_cast(addr_of(v));
return ::unsafe::reinterpret_cast(addr_of((**repr).data));
}
/**
* Form a slice from a pointer and length (as a number of units,
* not bytes).
*/
#[inline(always)]
unsafe fn form_slice<T,U>(p: *T, len: uint, f: fn(&& &[T]) -> U) -> U {
let pair = (p, len * sys::size_of::<T>());
let v : *(&blk/[T]) =
::unsafe::reinterpret_cast(ptr::addr_of(pair));
f(*v)
}
/**
* Unchecked vector indexing.
*/
#[inline(always)]
unsafe fn get<T: copy>(v: &[const T], i: uint) -> T {
as_buf(v, |p, _len| *ptr::offset(p, i))
}
/**
* Unchecked vector index assignment.
*/
#[inline(always)]
unsafe fn set<T>(v: &[mut T], i: uint, +val: T) {
let mut box = some(val);
do as_mut_buf(v) |p, _len| {
let mut box2 = none;
box2 <-> box;
rusti::move_val_init(*ptr::mut_offset(p, i),
option::unwrap(box2));
}
}
/**
* Copies data from one vector to another.
*
* Copies `count` bytes from `src` to `dst`. The source and destination
* may overlap.
*/
unsafe fn memcpy<T>(dst: &[mut T], src: &[const T], count: uint) {
do as_buf(dst) |p_dst, _len_dst| {
do as_buf(src) |p_src, _len_src| {
ptr::memcpy(p_dst, p_src, count)
}
}
}
/**
* Copies data from one vector to another.
*
* Copies `count` bytes from `src` to `dst`. The source and destination
* may overlap.
*/
unsafe fn memmove<T>(dst: &[mut T], src: &[const T], count: uint) {
do as_buf(dst) |p_dst, _len_dst| {
do as_buf(src) |p_src, _len_src| {
ptr::memmove(p_dst, p_src, count)
}
}
}
}
/// Operations on `[u8]`
mod u8 {
export cmp;
export lt, le, eq, ne, ge, gt;
export hash;
export memcpy, memmove;
/// Bytewise string comparison
pure fn cmp(&&a: ~[u8], &&b: ~[u8]) -> int {
let a_len = len(a);
let b_len = len(b);
let n = uint::min(a_len, b_len) as libc::size_t;
let r = unsafe {
libc::memcmp(unsafe::to_ptr(a) as *libc::c_void,
unsafe::to_ptr(b) as *libc::c_void, n) as int
};
if r != 0 { r } else {
if a_len == b_len {
0
} else if a_len < b_len {
-1
} else {
1
}
}
}
/// Bytewise less than or equal
pure fn lt(&&a: ~[u8], &&b: ~[u8]) -> bool { cmp(a, b) < 0 }
/// Bytewise less than or equal
pure fn le(&&a: ~[u8], &&b: ~[u8]) -> bool { cmp(a, b) <= 0 }
/// Bytewise equality
pure fn eq(&&a: ~[u8], &&b: ~[u8]) -> bool { unsafe { cmp(a, b) == 0 } }
/// Bytewise inequality
pure fn ne(&&a: ~[u8], &&b: ~[u8]) -> bool { unsafe { cmp(a, b) != 0 } }
/// Bytewise greater than or equal
pure fn ge(&&a: ~[u8], &&b: ~[u8]) -> bool { cmp(a, b) >= 0 }
/// Bytewise greater than
pure fn gt(&&a: ~[u8], &&b: ~[u8]) -> bool { cmp(a, b) > 0 }
/// Byte-vec hash function
fn hash(&&s: ~[u8]) -> uint {
hash::hash_bytes(s) as uint
}
/**
* Copies data from one vector to another.
*
* Copies `count` bytes from `src` to `dst`. The source and destination
* may not overlap.
*/
fn memcpy(dst: &[mut u8], src: &[const u8], count: uint) {
assert dst.len() >= count;
assert src.len() >= count;
unsafe { vec::unsafe::memcpy(dst, src, count) }
}
/**
* Copies data from one vector to another.
*
* Copies `count` bytes from `src` to `dst`. The source and destination
* may overlap.
*/
fn memmove(dst: &[mut u8], src: &[const u8], count: uint) {
assert dst.len() >= count;
assert src.len() >= count;
unsafe { vec::unsafe::memmove(dst, src, count) }
}
}
// ___________________________________________________________________________
// ITERATION TRAIT METHODS
//
// This cannot be used with iter-trait.rs because of the region pointer
// required in the slice.
impl extensions/&<A> of iter::base_iter<A> for &[A] {
fn each(blk: fn(A) -> bool) { each(self, blk) }
fn size_hint() -> option<uint> { some(len(self)) }
}
impl extensions/&<A> of iter::extended_iter<A> for &[A] {
fn eachi(blk: fn(uint, A) -> bool) { iter::eachi(self, blk) }
fn all(blk: fn(A) -> bool) -> bool { iter::all(self, blk) }
fn any(blk: fn(A) -> bool) -> bool { iter::any(self, blk) }
fn foldl<B>(+b0: B, blk: fn(B, A) -> B) -> B {
iter::foldl(self, b0, blk)
}
fn contains(x: A) -> bool { iter::contains(self, x) }
fn count(x: A) -> uint { iter::count(self, x) }
fn position(f: fn(A) -> bool) -> option<uint> { iter::position(self, f) }
}
trait iter_trait_extensions<A> {
fn filter_to_vec(pred: fn(A) -> bool) -> ~[A];
fn map_to_vec<B>(op: fn(A) -> B) -> ~[B];
fn to_vec() -> ~[A];
fn min() -> A;
fn max() -> A;
}
impl extensions/&<A:copy> of iter_trait_extensions<A> for &[A] {
fn filter_to_vec(pred: fn(A) -> bool) -> ~[A] {
iter::filter_to_vec(self, pred)
}
fn map_to_vec<B>(op: fn(A) -> B) -> ~[B] { iter::map_to_vec(self, op) }
fn to_vec() -> ~[A] { iter::to_vec(self) }
// FIXME--bug in resolve prevents this from working (#2611)
// fn flat_map_to_vec<B:copy,IB:base_iter<B>>(op: fn(A) -> IB) -> ~[B] {
// iter::flat_map_to_vec(self, op)
// }
fn min() -> A { iter::min(self) }
fn max() -> A { iter::max(self) }
}
// ___________________________________________________________________________
#[cfg(test)]
mod tests {
fn square(n: uint) -> uint { return n * n; }
fn square_ref(&&n: uint) -> uint { return n * n; }
pure fn is_three(&&n: uint) -> bool { return n == 3u; }
pure fn is_odd(&&n: uint) -> bool { return n % 2u == 1u; }
pure fn is_equal(&&x: uint, &&y:uint) -> bool { return x == y; }
fn square_if_odd(&&n: uint) -> option<uint> {
return if n % 2u == 1u { some(n * n) } else { none };
}
fn add(&&x: uint, &&y: uint) -> uint { return x + y; }
#[test]
fn test_unsafe_ptrs() {
unsafe {
// Test on-stack copy-from-buf.
let a = ~[1, 2, 3];
let mut ptr = unsafe::to_ptr(a);
let b = unsafe::from_buf(ptr, 3u);
assert (len(b) == 3u);
assert (b[0] == 1);
assert (b[1] == 2);
assert (b[2] == 3);
// Test on-heap copy-from-buf.
let c = ~[1, 2, 3, 4, 5];
ptr = unsafe::to_ptr(c);
let d = unsafe::from_buf(ptr, 5u);
assert (len(d) == 5u);
assert (d[0] == 1);
assert (d[1] == 2);
assert (d[2] == 3);
assert (d[3] == 4);
assert (d[4] == 5);
}
}
#[test]
fn test_from_fn() {
// Test on-stack from_fn.
let mut v = from_fn(3u, square);
assert (len(v) == 3u);
assert (v[0] == 0u);
assert (v[1] == 1u);
assert (v[2] == 4u);
// Test on-heap from_fn.
v = from_fn(5u, square);
assert (len(v) == 5u);
assert (v[0] == 0u);
assert (v[1] == 1u);
assert (v[2] == 4u);
assert (v[3] == 9u);
assert (v[4] == 16u);
}
#[test]
fn test_from_elem() {
// Test on-stack from_elem.
let mut v = from_elem(2u, 10u);
assert (len(v) == 2u);
assert (v[0] == 10u);
assert (v[1] == 10u);
// Test on-heap from_elem.
v = from_elem(6u, 20u);
assert (v[0] == 20u);
assert (v[1] == 20u);
assert (v[2] == 20u);
assert (v[3] == 20u);
assert (v[4] == 20u);
assert (v[5] == 20u);
}
#[test]
fn test_is_empty() {
assert (is_empty::<int>(~[]));
assert (!is_empty(~[0]));
}
#[test]
fn test_is_not_empty() {
assert (is_not_empty(~[0]));
assert (!is_not_empty::<int>(~[]));
}
#[test]
fn test_head() {
let a = ~[11, 12];
assert (head(a) == 11);
}
#[test]
fn test_tail() {
let mut a = ~[11];
assert (tail(a) == ~[]);
a = ~[11, 12];
assert (tail(a) == ~[12]);
}
#[test]
fn test_last() {
let mut n = last_opt(~[]);
assert (n == none);
n = last_opt(~[1, 2, 3]);
assert (n == some(3));
n = last_opt(~[1, 2, 3, 4, 5]);
assert (n == some(5));
}
#[test]
fn test_slice() {
// Test on-stack -> on-stack slice.
let mut v = slice(~[1, 2, 3], 1u, 3u);
assert (len(v) == 2u);
assert (v[0] == 2);
assert (v[1] == 3);
// Test on-heap -> on-stack slice.
v = slice(~[1, 2, 3, 4, 5], 0u, 3u);
assert (len(v) == 3u);
assert (v[0] == 1);
assert (v[1] == 2);
assert (v[2] == 3);
// Test on-heap -> on-heap slice.
v = slice(~[1, 2, 3, 4, 5, 6], 1u, 6u);
assert (len(v) == 5u);
assert (v[0] == 2);
assert (v[1] == 3);
assert (v[2] == 4);
assert (v[3] == 5);
assert (v[4] == 6);
}
#[test]
fn test_pop() {
// Test on-stack pop.
let mut v = ~[1, 2, 3];
let mut e = pop(v);
assert (len(v) == 2u);
assert (v[0] == 1);
assert (v[1] == 2);
assert (e == 3);
// Test on-heap pop.
v = ~[1, 2, 3, 4, 5];
e = pop(v);
assert (len(v) == 4u);
assert (v[0] == 1);
assert (v[1] == 2);
assert (v[2] == 3);
assert (v[3] == 4);
assert (e == 5);
}
#[test]
fn test_push() {
// Test on-stack push().
let mut v = ~[];
push(v, 1);
assert (len(v) == 1u);
assert (v[0] == 1);
// Test on-heap push().
push(v, 2);
assert (len(v) == 2u);
assert (v[0] == 1);
assert (v[1] == 2);
}
#[test]
fn test_grow() {
// Test on-stack grow().
let mut v = ~[];
grow(v, 2u, 1);
assert (len(v) == 2u);
assert (v[0] == 1);
assert (v[1] == 1);
// Test on-heap grow().
grow(v, 3u, 2);
assert (len(v) == 5u);
assert (v[0] == 1);
assert (v[1] == 1);
assert (v[2] == 2);
assert (v[3] == 2);
assert (v[4] == 2);
}
#[test]
fn test_grow_fn() {
let mut v = ~[];
grow_fn(v, 3u, square);
assert (len(v) == 3u);
assert (v[0] == 0u);
assert (v[1] == 1u);
assert (v[2] == 4u);
}
#[test]
fn test_grow_set() {
let mut v = ~[mut 1, 2, 3];
grow_set(v, 4u, 4, 5);
assert (len(v) == 5u);
assert (v[0] == 1);
assert (v[1] == 2);
assert (v[2] == 3);
assert (v[3] == 4);
assert (v[4] == 5);
}
#[test]
fn test_map() {
// Test on-stack map.
let mut v = ~[1u, 2u, 3u];
let mut w = map(v, square_ref);
assert (len(w) == 3u);
assert (w[0] == 1u);
assert (w[1] == 4u);
assert (w[2] == 9u);
// Test on-heap map.
v = ~[1u, 2u, 3u, 4u, 5u];
w = map(v, square_ref);
assert (len(w) == 5u);
assert (w[0] == 1u);
assert (w[1] == 4u);
assert (w[2] == 9u);
assert (w[3] == 16u);
assert (w[4] == 25u);
}
#[test]
fn test_map2() {
fn times(&&x: int, &&y: int) -> int { return x * y; }
let f = times;
let v0 = ~[1, 2, 3, 4, 5];
let v1 = ~[5, 4, 3, 2, 1];
let u = map2::<int, int, int>(v0, v1, f);
let mut i = 0;
while i < 5 { assert (v0[i] * v1[i] == u[i]); i += 1; }
}
#[test]
fn test_filter_map() {
// Test on-stack filter-map.
let mut v = ~[1u, 2u, 3u];
let mut w = filter_map(v, square_if_odd);
assert (len(w) == 2u);
assert (w[0] == 1u);
assert (w[1] == 9u);
// Test on-heap filter-map.
v = ~[1u, 2u, 3u, 4u, 5u];
w = filter_map(v, square_if_odd);
assert (len(w) == 3u);
assert (w[0] == 1u);
assert (w[1] == 9u);
assert (w[2] == 25u);
fn halve(&&i: int) -> option<int> {
if i % 2 == 0 {
return option::some::<int>(i / 2);
} else { return option::none::<int>; }
}
fn halve_for_sure(&&i: int) -> int { return i / 2; }
let all_even: ~[int] = ~[0, 2, 8, 6];
let all_odd1: ~[int] = ~[1, 7, 3];
let all_odd2: ~[int] = ~[];
let mix: ~[int] = ~[9, 2, 6, 7, 1, 0, 0, 3];
let mix_dest: ~[int] = ~[1, 3, 0, 0];
assert (filter_map(all_even, halve) == map(all_even, halve_for_sure));
assert (filter_map(all_odd1, halve) == ~[]);
assert (filter_map(all_odd2, halve) == ~[]);
assert (filter_map(mix, halve) == mix_dest);
}
#[test]
fn test_filter() {
assert filter(~[1u, 2u, 3u], is_odd) == ~[1u, 3u];
assert filter(~[1u, 2u, 4u, 8u, 16u], is_three) == ~[];
}
#[test]
fn test_foldl() {
// Test on-stack fold.
let mut v = ~[1u, 2u, 3u];
let mut sum = foldl(0u, v, add);
assert (sum == 6u);
// Test on-heap fold.
v = ~[1u, 2u, 3u, 4u, 5u];
sum = foldl(0u, v, add);
assert (sum == 15u);
}
#[test]
fn test_foldl2() {
fn sub(&&a: int, &&b: int) -> int {
a - b
}
let mut v = ~[1, 2, 3, 4];
let sum = foldl(0, v, sub);
assert sum == -10;
}
#[test]
fn test_foldr() {
fn sub(&&a: int, &&b: int) -> int {
a - b
}
let mut v = ~[1, 2, 3, 4];
let sum = foldr(v, 0, sub);
assert sum == -2;
}
#[test]
fn test_iter_empty() {
let mut i = 0;
iter::<int>(~[], |_v| i += 1);
assert i == 0;
}
#[test]
fn test_iter_nonempty() {
let mut i = 0;
iter(~[1, 2, 3], |v| i += v);
assert i == 6;
}
#[test]
fn test_iteri() {
let mut i = 0;
iteri(~[1, 2, 3], |j, v| {
if i == 0 { assert v == 1; }
assert j + 1u == v as uint;
i += v;
});
assert i == 6;
}
#[test]
fn test_riter_empty() {
let mut i = 0;
riter::<int>(~[], |_v| i += 1);
assert i == 0;
}
#[test]
fn test_riter_nonempty() {
let mut i = 0;
riter(~[1, 2, 3], |v| {
if i == 0 { assert v == 3; }
i += v
});
assert i == 6;
}
#[test]
fn test_riteri() {
let mut i = 0;
riteri(~[0, 1, 2], |j, v| {
if i == 0 { assert v == 2; }
assert j == v as uint;
i += v;
});
assert i == 3;
}
#[test]
fn test_permute() {
let mut results: ~[~[int]];
results = ~[];
permute(~[], |v| vec::push(results, v));
assert results == ~[~[]];
results = ~[];
permute(~[7], |v| results += ~[v]);
assert results == ~[~[7]];
results = ~[];
permute(~[1,1], |v| results += ~[v]);
assert results == ~[~[1,1],~[1,1]];
results = ~[];
permute(~[5,2,0], |v| results += ~[v]);
assert results ==
~[~[5,2,0],~[5,0,2],~[2,5,0],~[2,0,5],~[0,5,2],~[0,2,5]];
}
#[test]
fn test_any_and_all() {
assert (any(~[1u, 2u, 3u], is_three));
assert (!any(~[0u, 1u, 2u], is_three));
assert (any(~[1u, 2u, 3u, 4u, 5u], is_three));
assert (!any(~[1u, 2u, 4u, 5u, 6u], is_three));
assert (all(~[3u, 3u, 3u], is_three));
assert (!all(~[3u, 3u, 2u], is_three));
assert (all(~[3u, 3u, 3u, 3u, 3u], is_three));
assert (!all(~[3u, 3u, 0u, 1u, 2u], is_three));
}
#[test]
fn test_any2_and_all2() {
assert (any2(~[2u, 4u, 6u], ~[2u, 4u, 6u], is_equal));
assert (any2(~[1u, 2u, 3u], ~[4u, 5u, 3u], is_equal));
assert (!any2(~[1u, 2u, 3u], ~[4u, 5u, 6u], is_equal));
assert (any2(~[2u, 4u, 6u], ~[2u, 4u], is_equal));
assert (all2(~[2u, 4u, 6u], ~[2u, 4u, 6u], is_equal));
assert (!all2(~[1u, 2u, 3u], ~[4u, 5u, 3u], is_equal));
assert (!all2(~[1u, 2u, 3u], ~[4u, 5u, 6u], is_equal));
assert (!all2(~[2u, 4u, 6u], ~[2u, 4u], is_equal));
}
#[test]
fn test_zip_unzip() {
let v1 = ~[1, 2, 3];
let v2 = ~[4, 5, 6];
let z1 = zip(v1, v2);
assert ((1, 4) == z1[0]);
assert ((2, 5) == z1[1]);
assert ((3, 6) == z1[2]);
let (left, right) = unzip(z1);
assert ((1, 4) == (left[0], right[0]));
assert ((2, 5) == (left[1], right[1]));
assert ((3, 6) == (left[2], right[2]));
}
#[test]
fn test_position_elem() {
assert position_elem(~[], 1) == none;
let v1 = ~[1, 2, 3, 3, 2, 5];
assert position_elem(v1, 1) == some(0u);
assert position_elem(v1, 2) == some(1u);
assert position_elem(v1, 5) == some(5u);
assert position_elem(v1, 4) == none;
}
#[test]
fn test_position() {
fn less_than_three(&&i: int) -> bool { return i < 3; }
fn is_eighteen(&&i: int) -> bool { return i == 18; }
assert position(~[], less_than_three) == none;
let v1 = ~[5, 4, 3, 2, 1];
assert position(v1, less_than_three) == some(3u);
assert position(v1, is_eighteen) == none;
}
#[test]
fn test_position_between() {
assert position_between(~[], 0u, 0u, f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert position_between(v, 0u, 0u, f) == none;
assert position_between(v, 0u, 1u, f) == none;
assert position_between(v, 0u, 2u, f) == some(1u);
assert position_between(v, 0u, 3u, f) == some(1u);
assert position_between(v, 0u, 4u, f) == some(1u);
assert position_between(v, 1u, 1u, f) == none;
assert position_between(v, 1u, 2u, f) == some(1u);
assert position_between(v, 1u, 3u, f) == some(1u);
assert position_between(v, 1u, 4u, f) == some(1u);
assert position_between(v, 2u, 2u, f) == none;
assert position_between(v, 2u, 3u, f) == none;
assert position_between(v, 2u, 4u, f) == some(3u);
assert position_between(v, 3u, 3u, f) == none;
assert position_between(v, 3u, 4u, f) == some(3u);
assert position_between(v, 4u, 4u, f) == none;
}
#[test]
fn test_find() {
assert find(~[], f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
fn g(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'd' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert find(v, f) == some((1, 'b'));
assert find(v, g) == none;
}
#[test]
fn test_find_between() {
assert find_between(~[], 0u, 0u, f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert find_between(v, 0u, 0u, f) == none;
assert find_between(v, 0u, 1u, f) == none;
assert find_between(v, 0u, 2u, f) == some((1, 'b'));
assert find_between(v, 0u, 3u, f) == some((1, 'b'));
assert find_between(v, 0u, 4u, f) == some((1, 'b'));
assert find_between(v, 1u, 1u, f) == none;
assert find_between(v, 1u, 2u, f) == some((1, 'b'));
assert find_between(v, 1u, 3u, f) == some((1, 'b'));
assert find_between(v, 1u, 4u, f) == some((1, 'b'));
assert find_between(v, 2u, 2u, f) == none;
assert find_between(v, 2u, 3u, f) == none;
assert find_between(v, 2u, 4u, f) == some((3, 'b'));
assert find_between(v, 3u, 3u, f) == none;
assert find_between(v, 3u, 4u, f) == some((3, 'b'));
assert find_between(v, 4u, 4u, f) == none;
}
#[test]
fn test_rposition() {
assert find(~[], f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
fn g(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'd' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert position(v, f) == some(1u);
assert position(v, g) == none;
}
#[test]
fn test_rposition_between() {
assert rposition_between(~[], 0u, 0u, f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert rposition_between(v, 0u, 0u, f) == none;
assert rposition_between(v, 0u, 1u, f) == none;
assert rposition_between(v, 0u, 2u, f) == some(1u);
assert rposition_between(v, 0u, 3u, f) == some(1u);
assert rposition_between(v, 0u, 4u, f) == some(3u);
assert rposition_between(v, 1u, 1u, f) == none;
assert rposition_between(v, 1u, 2u, f) == some(1u);
assert rposition_between(v, 1u, 3u, f) == some(1u);
assert rposition_between(v, 1u, 4u, f) == some(3u);
assert rposition_between(v, 2u, 2u, f) == none;
assert rposition_between(v, 2u, 3u, f) == none;
assert rposition_between(v, 2u, 4u, f) == some(3u);
assert rposition_between(v, 3u, 3u, f) == none;
assert rposition_between(v, 3u, 4u, f) == some(3u);
assert rposition_between(v, 4u, 4u, f) == none;
}
#[test]
fn test_rfind() {
assert rfind(~[], f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
fn g(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'd' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert rfind(v, f) == some((3, 'b'));
assert rfind(v, g) == none;
}
#[test]
fn test_rfind_between() {
assert rfind_between(~[], 0u, 0u, f) == none;
fn f(xy: (int, char)) -> bool { let (_x, y) = xy; y == 'b' }
let mut v = ~[(0, 'a'), (1, 'b'), (2, 'c'), (3, 'b')];
assert rfind_between(v, 0u, 0u, f) == none;
assert rfind_between(v, 0u, 1u, f) == none;
assert rfind_between(v, 0u, 2u, f) == some((1, 'b'));
assert rfind_between(v, 0u, 3u, f) == some((1, 'b'));
assert rfind_between(v, 0u, 4u, f) == some((3, 'b'));
assert rfind_between(v, 1u, 1u, f) == none;
assert rfind_between(v, 1u, 2u, f) == some((1, 'b'));
assert rfind_between(v, 1u, 3u, f) == some((1, 'b'));
assert rfind_between(v, 1u, 4u, f) == some((3, 'b'));
assert rfind_between(v, 2u, 2u, f) == none;
assert rfind_between(v, 2u, 3u, f) == none;
assert rfind_between(v, 2u, 4u, f) == some((3, 'b'));
assert rfind_between(v, 3u, 3u, f) == none;
assert rfind_between(v, 3u, 4u, f) == some((3, 'b'));
assert rfind_between(v, 4u, 4u, f) == none;
}
#[test]
fn reverse_and_reversed() {
let v: ~[mut int] = ~[mut 10, 20];
assert (v[0] == 10);
assert (v[1] == 20);
reverse(v);
assert (v[0] == 20);
assert (v[1] == 10);
let v2 = reversed::<int>(~[10, 20]);
assert (v2[0] == 20);
assert (v2[1] == 10);
v[0] = 30;
assert (v2[0] == 20);
// Make sure they work with 0-length vectors too.
let v4 = reversed::<int>(~[]);
assert (v4 == ~[]);
let v3: ~[mut int] = ~[mut];
reverse::<int>(v3);
}
#[test]
fn reversed_mut() {
let v2 = reversed::<int>(~[mut 10, 20]);
assert (v2[0] == 20);
assert (v2[1] == 10);
}
#[test]
fn test_init() {
let v = init(~[1, 2, 3]);
assert v == ~[1, 2];
}
#[test]
fn test_split() {
fn f(&&x: int) -> bool { x == 3 }
assert split(~[], f) == ~[];
assert split(~[1, 2], f) == ~[~[1, 2]];
assert split(~[3, 1, 2], f) == ~[~[], ~[1, 2]];
assert split(~[1, 2, 3], f) == ~[~[1, 2], ~[]];
assert split(~[1, 2, 3, 4, 3, 5], f) == ~[~[1, 2], ~[4], ~[5]];
}
#[test]
fn test_splitn() {
fn f(&&x: int) -> bool { x == 3 }
assert splitn(~[], 1u, f) == ~[];
assert splitn(~[1, 2], 1u, f) == ~[~[1, 2]];
assert splitn(~[3, 1, 2], 1u, f) == ~[~[], ~[1, 2]];
assert splitn(~[1, 2, 3], 1u, f) == ~[~[1, 2], ~[]];
assert splitn(~[1, 2, 3, 4, 3, 5], 1u, f) ==
~[~[1, 2], ~[4, 3, 5]];
}
#[test]
fn test_rsplit() {
fn f(&&x: int) -> bool { x == 3 }
assert rsplit(~[], f) == ~[];
assert rsplit(~[1, 2], f) == ~[~[1, 2]];
assert rsplit(~[1, 2, 3], f) == ~[~[1, 2], ~[]];
assert rsplit(~[1, 2, 3, 4, 3, 5], f) == ~[~[1, 2], ~[4], ~[5]];
}
#[test]
fn test_rsplitn() {
fn f(&&x: int) -> bool { x == 3 }
assert rsplitn(~[], 1u, f) == ~[];
assert rsplitn(~[1, 2], 1u, f) == ~[~[1, 2]];
assert rsplitn(~[1, 2, 3], 1u, f) == ~[~[1, 2], ~[]];
assert rsplitn(~[1, 2, 3, 4, 3, 5], 1u, f) ==
~[~[1, 2, 3, 4], ~[5]];
}
#[test]
#[should_fail]
#[ignore(cfg(windows))]
fn test_init_empty() {
init::<int>(~[]);
}
#[test]
fn test_concat() {
assert concat(~[~[1], ~[2,3]]) == ~[1, 2, 3];
}
#[test]
fn test_connect() {
assert connect(~[], 0) == ~[];
assert connect(~[~[1], ~[2, 3]], 0) == ~[1, 0, 2, 3];
assert connect(~[~[1], ~[2], ~[3]], 0) == ~[1, 0, 2, 0, 3];
}
#[test]
fn test_windowed () {
assert ~[~[1u,2u,3u],~[2u,3u,4u],~[3u,4u,5u],~[4u,5u,6u]]
== windowed (3u, ~[1u,2u,3u,4u,5u,6u]);
assert ~[~[1u,2u,3u,4u],~[2u,3u,4u,5u],~[3u,4u,5u,6u]]
== windowed (4u, ~[1u,2u,3u,4u,5u,6u]);
assert ~[] == windowed (7u, ~[1u,2u,3u,4u,5u,6u]);
}
#[test]
#[should_fail]
#[ignore(cfg(windows))]
fn test_windowed_() {
let _x = windowed (0u, ~[1u,2u,3u,4u,5u,6u]);
}
#[test]
fn to_mut_no_copy() {
unsafe {
let x = ~[1, 2, 3];
let addr = unsafe::to_ptr(x);
let x_mut = to_mut(x);
let addr_mut = unsafe::to_ptr(x_mut);
assert addr == addr_mut;
}
}
#[test]
fn from_mut_no_copy() {
unsafe {
let x = ~[mut 1, 2, 3];
let addr = unsafe::to_ptr(x);
let x_imm = from_mut(x);
let addr_imm = unsafe::to_ptr(x_imm);
assert addr == addr_imm;
}
}
#[test]
fn test_unshift() {
let mut x = ~[1, 2, 3];
unshift(x, 0);
assert x == ~[0, 1, 2, 3];
}
#[test]
fn test_capacity() {
let mut v = ~[0u64];
reserve(v, 10u);
assert capacity(v) == 10u;
let mut v = ~[0u32];
reserve(v, 10u);
assert capacity(v) == 10u;
}
/*
#[test]
#[ignore] // region inference doesn't work well enough for this yet.
fn test_view() {
let v = ~[1, 2, 3, 4, 5];
let v = view(v, 1u, 3u);
assert(len(v) == 2u);
assert(v[0] == 2);
assert(v[1] == 3);
}
*/
}
// Local Variables:
// mode: rust;
// fill-column: 78;
// indent-tabs-mode: nil
// c-basic-offset: 4
// buffer-file-coding-system: utf-8-unix
// End:
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