Menge: Type-safe sets for Go

Overview

Note: Menge was created before the introduction of generics in Go 1.18. Such an implementation is not necessary anymore.

Menge implements type-safe sets of all basic types:

• String: StringSet
• Integer: IntSet, Int8Set, Int16Set, Int32Set, Int64Set
• Unsigned integer: UIntSet, UInt8Set, UInt16Set, UInt32Set, UInt64Set, UIntPtrSet
• Float: Float32Set, Float64Set
• Complex: Complex64Set, Complex128Set

Note that there are no set types for byte and rune, as they are just aliases for uint8 and int32. Also, there is no practical use to a set of type bool.

Concurrency

Menge sets use Go maps as their underlying data structure. As a result, these sets are not safe for concurrent use. You can protect them with sync.RWMutex. Read the Concurrency section of this article for more details.

Example

You can run this example on the Go Playground.

package main

import (
	"fmt"
	"github.com/soroushj/menge"
)

func main() {
	s := menge.NewIntSet(1, 2, 3)
	fmt.Println("Set:", s)
	for e := range s {
		fmt.Println("Element:", e)
	}
	fmt.Println("Remove 1, 2; add 3, 4")
	s.Remove(1, 2)
	s.Add(3, 4)
	fmt.Println("Has 1?", s.Has(1))
	fmt.Println("Size:", s.Size())
	c := s.Clone()
	fmt.Printf("Clone: %v (%T)\n", c, c)
	l := s.AsSlice()
	fmt.Printf("Slice: %v (%T)\n", l, l)
	fmt.Println("Empty")
	s.Empty()
	fmt.Println("Is empty?", s.IsEmpty())
	a := menge.NewIntSet(1)
	b := menge.NewIntSet(1, 2)
	fmt.Printf("Does %v equal %v? %v\n", a, b, a.Equals(b))
	fmt.Printf("Is %v a subset of %v? %v\n", a, b, a.IsSubsetOf(b))
	fmt.Printf("Is %v a proper subset of %v? %v\n", a, b, a.IsProperSubsetOf(b))
	fmt.Printf("Is %v a superset of %v? %v\n", a, b, a.IsSupersetOf(b))
	fmt.Printf("Is %v a proper superset of %v? %v\n", a, b, a.IsProperSupersetOf(b))
	fmt.Printf("Are %v and %v disjoint? %v\n", a, b, a.IsDisjointFrom(b))
	fmt.Printf("%v ⋃ %v = %v\n", a, b, a.Union(b))
	fmt.Printf("%v ⋂ %v = %v\n", a, b, a.Intersection(b))
	fmt.Printf("%v - %v = %v\n", a, b, a.Difference(b))
}