Module

pooka/set

src/pooka/set.pooka

A set keeps one chair for each distinct guest.

Store membership through an immutable dictionary with Nil values. Set operations return new sets, enumeration order is unspecified, and equals compares membership rather than the identity of captured storage closures.

import pooka/set

assert set.from_list([1, 1, 2]).size() == 2

API reference

classSet
functionempty
functionfrom_list

class

Set

src/pooka/set.pooka:22

class Set(a)

An immutable membership collection. Equality of contents is provided by equals; storage handles themselves have identity.

constructor

new

src/pooka/set.pooka:27

new(values: Dict(a, Nil))

INFERREDfn(pooka/dict.Dict(a, Nil)) -> pooka/set.Set(a)

Create the value from its declared fields. Public factory functions keep the storage details out of ordinary calling code.

method

to_list

src/pooka/set.pooka:39

to_list() -> List(a)

INFERREDfn() -> List(a)

Enumerate members in unspecified order.

import pooka/list
import pooka/set

assert list.contains(set.from_list([1, 2]).to_list(), 1)

method

insert

src/pooka/set.pooka:50

insert(value: a) -> Set(a)

INFERREDfn(a) -> pooka/set.Set(a)

Return a set containing the value.

import pooka/set

assert set.empty().insert(1).contains(1)

method

delete

src/pooka/set.pooka:61

delete(value: a) -> Set(a)

INFERREDfn(a) -> pooka/set.Set(a)

Return a set without the value; absence is harmless.

import pooka/set

assert set.from_list([1]).delete(1).is_empty()

method

contains

src/pooka/set.pooka:72

contains(value: a) -> Bool

INFERREDfn(a) -> Bool

Check whether a value is a member.

import pooka/set

assert set.from_list([1, 2]).contains(2)

method

size

src/pooka/set.pooka:83

size() -> Int

INFERREDfn() -> Int

Count distinct members.

import pooka/set

assert set.from_list([1, 1, 2]).size() == 2

method

is_empty

src/pooka/set.pooka:94

is_empty() -> Bool

INFERREDfn() -> Bool

Ask whether the set has no members.

import pooka/set

assert set.empty().is_empty()

method

union

src/pooka/set.pooka:105

union(right: Set(a)) -> Set(a)

INFERREDfn(pooka/set.Set(a)) -> pooka/set.Set(a)

Keep members present in either set.

import pooka/set

assert set.from_list([1]).union(set.from_list([2])).size() == 2

method

intersection

src/pooka/set.pooka:116

intersection(right: Set(a)) -> Set(a)

INFERREDfn(pooka/set.Set(a)) -> pooka/set.Set(a)

Keep members present in both sets.

import pooka/set

assert set.from_list([1, 2]).intersection(set.from_list([2, 3])).equals(set.from_list([2]))

method

difference

src/pooka/set.pooka:127

difference(right: Set(a)) -> Set(a)

INFERREDfn(pooka/set.Set(a)) -> pooka/set.Set(a)

Keep left-hand members absent from the right-hand set.

import pooka/set

assert set.from_list([1, 2]).difference(set.from_list([2])).equals(set.from_list([1]))

method

equals

src/pooka/set.pooka:139

equals(right: Set(a)) -> Bool

INFERREDfn(pooka/set.Set(a)) -> Bool

Compare membership rather than the identity of captured dictionary storage.

import pooka/set

assert set.from_list([1, 2]).equals(set.from_list([2, 1]))

method

is_subset

src/pooka/set.pooka:150

is_subset(right: Set(a)) -> Bool

INFERREDfn(pooka/set.Set(a)) -> Bool

Require every member of this set to belong to the right-hand set.

import pooka/set

assert set.from_list([1]).is_subset(set.from_list([1, 2]))

function

empty

src/pooka/set.pooka:162

empty() -> Set(a)

INFERREDfn() -> pooka/set.Set(a)

Open an empty set.

import pooka/set

assert set.empty().is_empty()

function

from_list

src/pooka/set.pooka:173

from_list(values: List(a)) -> Set(a)

INFERREDfn(List(a)) -> pooka/set.Set(a)

Build membership from a list, forgetting repeated values.

import pooka/set

assert set.from_list([1, 1, 2]).size() == 2