A [Red-Black Tree](https://en.wikipedia.org/wiki/Red%E2%80%93black_tree) [Hash Map](https://en.wikipedia.org/wiki/Hash_table) implementation in Golang that uses user-supplied hashing algorithms.
## Usage
The hashmap supports the classic Get, Insert, Remove operations you'd expect.
### Inserting
```go
//hash function must take interface{} and return int64
hashFunc := func(i interface{}) int64 {
return int64(i.(int))
}
m := hashmap.New(hashFunc)
//insertion of key, value. keep in mind the key will be used as input to your hashFunc
m.Insert(4, 0)
//you can store different types
m.Insert(19, "hello")
//panics, because the hashFunc doesn't support string keys
m.Insert("fail", "oh no")
```
### Selecting
```go
hashFunc := func(i interface{}) int64 {
return int64(i.(int))
}
m := hashmap.New(hashFunc)
m.Insert(4, 0)
m.Insert(19, 10)
//returns value as interface{} and found flag (true if the key was found)
value, found := m.Get(19)
// found will be false
value, found = m.Get(123)
```
### Removing
```go
hashFunc := func(i interface{}) int64 {
return int64(i.(int))
}
m := hashmap.New(hashFunc)
m.Insert(4, 0)
m.Insert(19, 10)
//returns found flag (true if the key was found)
found := m.Remove(19)
// found will be false
found = m.Remove(123)
```
## Type safety concerns
As this hash map supports keys and values of any type (by type hinting interface{}), there could be concerns of type safety and runtime problems. The suggested way to work around this is to wrap the hash map into type-specific proxy with methods such as `Get(key KeyType) (value ValueType, found bool)` and do the type assertions there.
Direct support for code generation by this package is still considered but not yet implemented.
