cp.collect.Set.md

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An implementation of a logical set, which contains a single unique reference of each item in it. For example:

Set(1,2,2,3) == Set(1,1,2,3,3) == Set(1,2,3)

You can combine sets in a couple of ways. For example, a union:

Set(1,2):union(Set(2,3)) == Set(1,2,3)
Set(1,2) | Set(2,3) == Set(1,2,3)

...or an intersection:

Set(1,2):intersection(Set(2,3)) == Set(2)
Set(1,2) & Set(2,3) == Set(2)

As indicated above, you can use operators for common set operations. Specifically:

• union (A ⋃ B): a | b or a + b
• intersection (A ∩ B): a & b
• complement (A^c): -a
• difference (A - B): a - b
• symetric difference (A ⊕ B) a ~ b

Keep in mind that Lua's operator precedence may be different to that of standard set operations, so it's probably best to group operations in brackets if you combine more than one in a single statement. For example:

a + b | c ~= a + (b | c)

API Overview

• Constants - Useful values which cannot be changed
• everything
• nothing
• Functions - API calls offered directly by the extension
• complement
• difference
• has
• intersection
• is
• isComplement
• size
• symetricDifference
• union
• Constructors - API calls which return an object, typically one that offers API methods
• clone
• fromList
• fromMap
• of
• Methods - API calls which can only be made on an object returned by a constructor
• complement
• difference
• has
• intersection
• isComplement
• size
• symetricDifference
• union

API Documentation

Constants

everything

Signature	cp.collect.Set.everything <cp.collect.Set>
Type	Constant
Description	A Set which contains the whole universe.

nothing

Signature	cp.collect.Set.nothing <cp.collect.Set>
Type	Constant
Description	An empty Set.

Functions

complement

Signature	cp.collect.Set.complement(set) -> cp.collect.Set
Type	Function
Description	Returns a Set which is the complement of the provided set.
Parameters	set - The Set to complement.
Returns	The new Set.

difference

Signature	cp.collect.Set.difference(left, right) -> cp.collect.Set
Type	Function
Description	Returns a new Set which is the set of values in left that are not in right.
Parameters	left - The left Set. right - The right Set.
Returns	The new Set.

has

Signature	cp.collect.Set.has(set, value) -> boolean
Type	Function
Description	Checks if the set has the specified value.
Parameters	set - The Set to check. value - The value to check for.
Returns	true if the value is contained in the Set.

intersection

Signature	cp.collect.Set.intersection(left, right) -> cp.collect.Set
Type	Function
Description
Parameters	left - The left Set right - The right Set.
Returns	A new Set which contains an intersection left and right.

is

Signature	cp.collect.Set.is(thing) -> boolean
Type	Function
Description	Checks if the thing is a Set.
Parameters	thing - The thing to check.
Returns	true if it is a Set.

isComplement

Signature	cp.collect.Set.isComplement(set) -> boolean
Type	Function
Description	Checks if the set is a complement set.
Parameters	set - The set to check.
Returns	true if the set is a complement.

size

Signature	cp.collect.Set.size(set) -> number
Type	Function
Description	Returns the size of the set.
Parameters	set - The set to find the size of.
Returns	the number of values in the set, or the number of values removed from a complement set.
Notes	If the set is empty, 0 is returned. If the set is a complement, this will return a negative number indicating how many values have been removed from the universal set of all things. If the set is a complement of an empty set, nil is returned to indicate the size is infinite.

symetricDifference

Signature	cp.collect.Set.symetricDifference(left, right) -> cp.collect.Set
Type	Function
Description	Performs a symetric difference of keys with a value of true in the left and right table into a new table.
Parameters	left - The left Set. right - The right Set.
Returns	The new Set.

union

Signature	cp.collect.Set.union(left, right) -> cp.collect.Set
Type	Function
Description	Returns a new Set which is a union of the left and right
Parameters	left - The left Set. right - The right Set.
Returns	A new Set which contains a union of the left and right Sets.

Constructors

clone

Signature	cp.collect.Set.clone(set) -> cp.collect.Set
Type	Constructor
Description	Creates a new Set which is a clone of the provided Set.
Parameters	set - The set to clone.
Returns	The new Set instance.

fromList

Signature	cp.collect.Set.fromList(list) -> cp.collect.Set
Type	Constructor
Description	Creates a new Set instance, containing the unique items in the table collected as a list from 1 to n.
Parameters	list - The table that contains items as a list to add to the Set. E.g. `{"foo", "bar"}
Returns	The new Set.

fromMap

Signature	cp.collect.Set.fromMap(map) -> cp.collect.Set
Type	Constructor
Description	Creates a new Set instance, containing the items in the provided table who's key value is true.
Parameters	map - The table that contains key/value items to add to the set. E.g. {foo = true, bar = true}
Returns	The new Set.

of

Signature	cp.collect.Set.of(...) -> cp.collect.Set
Type	Constructor
Description	Creates a new Set instance, containing the items in the parameter list.
Parameters	The set items.
Returns	The new Set instance.

Methods

complement

Signature	cp.collect.Set:complement() -> cp.collect.Set
Type	Method
Description	Returns a new Set which is the complement of the current Set.
Parameters	None
Returns	The new Set.
Notes	You can also use the - or ~ prefix operators. E.g. -a or ~a.

difference

Signature	cp.collect.Set:difference(right) -> cp.collect.Set
Type	Method
Description	Returns a new Set which is the set of values in this Set that are not in right.
Parameters	right - The right Set.
Returns	The new Set.
Notes	You can also use the - operator. E.g. a - b.

has

Signature	cp.collect.Set:has(value) -> boolean
Type	Method
Description	Checks if this set has the specified value.
Parameters	value - The value to check for.
Returns	true if the Set contains the value.
Notes	You can also check for specific values via mySet['key'] or mySet.key.

intersection

Signature	cp.collect.Set:intersection(...) -> cp.collect.Set
Type	Method
Description	Creates a new Set which is an intersection of the current values plus other Sets passed in.
Parameters	... - The list of Sets to create an intersection from.
Returns	The new Set.
Notes	You can also use the & operator. E.g. a & b.

isComplement

Signature	cp.collect.Set:isComplement() -> boolean
Type	Method
Description	Checks if the set is a complement set.
Parameters	None
Returns	true if the set is a complement.

size

Signature	cp.collect.Set:size() -> number
Type	Method
Description	Returns the size of the Set. If the set is a complement, this will return a negative number indicating
Parameters	None
Returns	the number of values in the set, or the number of values removed from a complement set.
Notes	If the set is empty, 0 is returned. If the set is a complement, this will return a negative number indicating how many values have been removed from the universal set of all things. If the set is a complement of an empty set, nil is returned to indicate the size is infinite.

symetricDifference

Signature	cp.collect.Set:symetricDifference(right) -> cp.collect.Set
Type	Method
Description	Performs a symetric difference of keys with a value of true in the left and right table into a new table.
Parameters	right - The right Set.
Returns	The new Set.
Notes	You can also use the ~ operator. E.g. a ~ b.

union

Signature	cp.collect.Set:union(...) -> cp.collect.Set
Type	Method
Description	Creates a new set which is a union of the current set plus other Sets passed in.
Parameters	... - The list of Sets to create a union from.
Returns	The new Set which is a union.
Notes	You can also use the | or + operator. E.g. a | b or a + b.