# cp.collect.Set

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)

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

| | | | --------------------------------------------|-------------------------------------------------------------------------------------| | 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. Any duplicate items will only occur in the Set once. | | Parameters |

• list - The table that contains items as a list to add to the Set. E.g. {"foo", "bar"}</li></ul> | | **Returns** | <ul><li>The new Set`.