Counter

class

@DebugEntries Public Class Counter<T: Hashable> Implements Iterable<(T, Int)>, Cloneable, Defaultable, Hashable

Local words = Counter<String>()
words.AddAll(["the", "cat", "the", "hat", "the"])
Expect(words["the"] == 3)
Expect(words["dog"] == 0)
Expect(words.Count == 3)
Expect(words.Total == 5)

std/collections/counter.fb, line 23

• Public New() constructor #

  A new, empty Counter.

• Public Property Count: Int property #

  How many values it counts, each once.

• Public Property Total: Int64 property #

  All the counts added up, which can be more than an Int holds.

• @PanicsAtCaller Public Method Add(value: T) method #

  Counts the value once more.

• @PanicsAtCaller Public Method Add(value: T, times: Int) method #

  Counts the value times more times. A negative times panics, and so does a count past what an Int holds, which only Total can be.

• @PanicsAtCaller Public Method AddAll(values: Iterable<T>) method #

  Counts each of the values once more, all read first.

• Public Method Remove(value: T): Bool method #

  Counts the value once less, and tells whether it was there.

• @PanicsAtCaller Public Method Remove(value: T, times: Int): Int method #

  Counts the value up to times less, and gives how many it took away. A negative times panics.

• Operator [](value: T): Int operator #

  How many times the value was counted, or 0.

• @PanicsAtCaller Operator []=(value: T, count: Int) operator #

  Gives the value a count, and a count of 0 removes it. A negative count panics.

• Public Method Contains(value: T): Bool method #

  Whether value has a count.

• Public Method Clear() method #

  Takes every count out.

• @PanicsAtCaller Public Method MostCommon(count: Int): (T, Int)[] method #

  The count most counted values and their counts, most first, and values counted the same number of times in the Counter's order. A negative count panics.

  Examples

  Copy

  Local letters = Counter<String>()
  letters.AddAll(["b", "a", "b", "c", "a", "b"])
  Expect(letters.MostCommon(2) == [("b", 3), ("a", 2)])

• Public Method Values(): T[] method #

  The values, each once, in the order they were added, one that came back last.

• Public Static Method DefaultValue(): Counter<T> static method #

  A new, empty Counter.

• Public Method Clone(): Counter<T> method #

  A new Counter with the same counts.

• Operator ==(a: Counter<T>, b: Counter<T>): Bool operator #

  Two Counters are equal when they count the same values the same number of times, in any order.

• Public Method Hash(): UInt64 method #

  A hash of its values and their counts, which Counters that are equal share.

• Public Method Iterate(): MapIterator<T, Int> method #

  Each value and its count, for 'For value, count In counter'. Changing a count while going over them is fine, but adding or removing a value panics.