bijective_map.go

package container

type BijectiveMap[A, B comparable] struct {
    m1 map[A]B
    m2 map[B]A
}

func (m *BijectiveMap[A, B]) GetB(a A) (B, bool) {
    if m.m1 == nil {
        var zero B
        return zero, false
    }    
    b, exists := m.m1[a]
    return b, exists
}

func (m *BijectiveMap[A, B]) GetA(b B) (A, bool) {
    if m.m2 == nil {
        var zero A
        return zero, false
    }    
    a, exists := m.m2[b]
    return a, exists
}

func (m *BijectiveMap[A, B]) Set(a A, b B) (A, B, bool) {
    if m.m1 == nil {
        m.m1 = make(map[A]B)
        m.m2 = make(map[B]A)
    }
    ob, exists := m.m1[a]
    if ob == b {
        return a, b, true
    }
    if exists {
        delete(m.m2, ob)
    }
    m.m1[a] = b
    m.m2[b] = a
    return a, ob, exists
}

func (m *BijectiveMap[A, B]) DelB(a A) (B, bool) {
    if m.m1 == nil {
        var zero B
        return zero, false
    }
    b, exists := m.m1[a]
    if exists {
        delete(m.m1, a)
        delete(m.m2, b)
    }
    return b, exists
}

func (m *BijectiveMap[A, B]) DelA(b B) (A, bool) {
    if m.m2 == nil {
        var zero A
        return zero, false
    }    
    a, exists := m.m2[b]
    if exists {
        delete(m.m1, a)
        delete(m.m2, b)
    }
    return a, exists
}

func (m *BijectiveMap[A, B]) ForEach(fn func(A, B) bool) {
    for k, v := range m.m1 {
        if !fn(k, v) {
            return
        }
    }
}