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API Documentation
- frostcollections Array Collection CollectionView CollectionWriter DefaultHashMap HashKey HashMap HashSet IdentityMap IdentitySet ImmutableArray Iterable Iterator List ListView ListWriter Map MapView MapWriter Stack core Bit Char16 Char32 Char8 Comparable Equatable Error Formattable Immutable Int Int16 Int32 Int64 Int8 Matcher Maybe MutableString Index MutableValue Object Range Real32 Real64 RegularExpression SteppedRange String Index Match System Process UInt UInt16 UInt32 UInt64 UInt8 Value Weak io ByteOrder Console File IndentedOutputStream InputStream LineNumberInputStream MemoryInputStream MemoryOutputStream OutputStream PushbackInputStream math Random XorShift128Plus threads Lock MessageQueue Notifier ScopedLock Thread time Timer unsafe Pointer UnsafeMessageQueue

frost.collections

Interface ListView<T>

Implemented Interfaces:

CollectionView<T>

A random-access CollectionView with numbered elements. Each entry has an index, ranging from 0 to count - 1, by which it can be accessed.

See also:: ListWriter
List

Source Code:: View Source

Field Summary

enumeration:Iterator<(frost.core.Int, frost.collections.ListView.T)>: Returns an Iterator which returns (index, value) tuples.
permutations:Iterator<ListView<T>>: An Iterator of all possible permutations of this list.
powerSet:Iterator<ListView<T>>: Returns an Iterator which produces the elements of the power set of this list.
last:T

Inherited Fields:

toString

Instance Method Summary

-- index operator -- [](index:Int):T: Returns an item from this list.
-- index operator -- [](r:Range<Int>):ListView<T>: Returns a slice of the list, containing all of the elements specified by the range.
-- index operator -- [](r:Range<Int?>):ListView<T>: Returns a slice of the list, containing all of the elements specified by the range.
-- index operator -- [](r:SteppedRange<Int?, Int>):ListView<T>: Returns a slice of the list, containing all of the elements specified by the range.
filter(predicate:(T)=>(Bit)):ListView<T>: Returns a new list containing every entry in this list for which the predicate function returns true.
filter(predicate:(T)=&>(Bit)):ListView<T>
combine(other:ListView):ListView<(frost.collections.ListView.T, frost.collections.ListView.combine.U)>
combine<U, V>(other:ListView, f:(T, U)=>(V)):ListView<V>
combine<U, V>(other:ListView, f:(T, U)=&>(V)):ListView<V>
combinations(n:Int):Iterator<ListView<T>>: Returns an Iterator of all possible n-combinations of this list.
sort(greater:(T, T)=>(Bit)):ListView<T>: Returns a sorted copy of the list using the provided comparison method.

Inherited Methods:

map((T)=&>(U)):Array
map((T)=>(U)):Array
apply((T)=&>())
fold((T, T)=&>(T), T):T
fold((T, T)=>(T), T):T
fold((T, T)=&>(T)):T
fold((T, T)=>(T)):T
join(String):String
join():String

Fields

property enumeration:Iterator<(frost.core.Int, frost.collections.ListView.T)>

Returns an Iterator which returns (index, value) tuples. For example, ["Hello", "Bonjour"].enumeration returns an Iterator<(Int, String)> which produces (0, "Hello") followed by (1, "Bonjour").

property permutations:Iterator<ListView<T>>

An Iterator of all possible permutations of this list. A permutation is a distinct ordering; each possible shuffling of a deck of cards is a different permutation. As the number of permutations is equal to the factorial of the number of elements in the list, it is only practical to fully iterate the permutations of very small lists (a list with just 15 elements in it has over a trillion permutations).

property powerSet:Iterator<ListView<T>>

Returns an Iterator which produces the elements of the power set of this list. The power set of a list is the set of all possible subsets (including the empty list). For instance, the power set of [1, 2, 3] is: [], [1], [2], [1, 2], [3], [1, 3], [2, 3], [1, 2, 3]. The iteration order is not guaranteed.

As the power set of a list with n elements contains 2^n entries, iterating over the power set is only practical for small lists.

property last:T

Instance Methods

-- index operator --
@pre(index >= 0 & index < count)

function []

(index:Int
):T

Returns an item from this list.

Parameters:: index - the (zero-based) index of the item to return

-- index operator --
@default
@pre(r.min >= 0 & (r.inclusive & r.min < count | !r.inclusive & r.min <= count) &
                        r.max >= 0 & (r.inclusive & r.max < count | !r.inclusive & r.max <= count))

function []

(r:Range<Int>
):ListView<T>

Returns a slice of the list, containing all of the elements specified by the range. The slice is an independent copy of the list and elements may be added to and removed from the original without affecting the copy. It is not, however, a deep copy, and thus both lists will refer to the same objects.

Parameters:: r - value of type Range<Int>

-- index operator --
@default

function []

(r:Range<Int?>
):ListView<T>

As usual for Range, a null min starts from the beginning of the list, and a null max ends at the end of the list.

Parameters:: r - value of type Range<Int?>

-- index operator --
@default
@pre(inRange(r, count))

function []

(r:SteppedRange<Int?, Int>
):ListView<T>

Parameters:: r - value of type SteppedRange<Int?, Int>

@default

function filter

(predicate:(T)=>(Bit)
):ListView<T>

Returns a new list containing every entry in this list for which the predicate function returns true. For instance, [1, 7, -10, 5, -2].filter(x => x > 0) returns [1, 7, 5].

Parameters:: predicate - value of type (T)=>(Bit)

@default

method filter

(predicate:(T)=&>(Bit)
):ListView<T>

Parameters:: predicate - value of type (T)=&>(Bit)

@default
@pre(count = other.count)

function combine<U>

(other:ListView<U>
):ListView<(frost.collections.ListView.T, frost.collections.ListView.combine.U)>

Parameters:: other - value of type ListView

@default
@pre(count = other.count)

function combine<U, V>

(other:ListView<U>,
 f:(T, U)=>(V)
):ListView<V>

Parameters:: other - value of type ListView
f - value of type (T, U)=>(V)

@default
@pre(count = other.count)

method combine<U, V>

(other:ListView<U>,
 f:(T, U)=&>(V)
):ListView<V>

Parameters:: other - value of type ListView
f - value of type (T, U)=&>(V)

@default
@pre(count >= n)

function combinations

(n:Int
):Iterator<ListView<T>>

Returns an Iterator of all possible n-combinations of this list. An n-combination of a list is a selection of n distinct elements from the list; the set of 5-combinations of a deck of cards is the set of all possible poker hands. The combinations are chosen in such a way as to preserve order: the combinations of a sorted list will themselves be sorted. Elements are considered "distinct" if they appear at different positions in the input list. This means that the 2-combinations of [1, 2, 2] are [1, 2], [1, 2], and [2, 2], as the two occurrences of 2 are considered distinct elements.

Parameters:: n - value of type Int

Returns:: an iterator which produces the n-combinations of this list

@default

method sort

(greater:(T, T)=>(Bit)
):ListView<T>

Returns a sorted copy of the list using the provided comparison method. The list is sorted so that the greatest elements, according to the greater function, are at the end (higher indices) of the array. The sort algorithm used may be unstable, meaning equal values (that is, values for which greater(a, b) and greater(b, a) both return false) may be arbitrarily reordered during the sort.

Parameters:: greater - value of type (T, T)=>(Bit)