gods/maps/treemap/enumerable.go

/*
Copyright (c) 2015, Emir Pasic
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

* Redistributions of source code must retain the above copyright notice, this
  list of conditions and the following disclaimer.

* Redistributions in binary form must reproduce the above copyright notice,
  this list of conditions and the following disclaimer in the documentation
  and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

package treemap

import (
	"github.com/emirpasic/gods/containers"
	rbt "github.com/emirpasic/gods/trees/redblacktree"
)

func assertEnumerableImplementation() {
	var _ containers.EnumerableWithKey = (*Map)(nil)
}

// Each calls the given function once for each element, passing that element's key and value.
func (m *Map) Each(f func(key interface{}, value interface{})) {
	iterator := m.Iterator()
	for iterator.Next() {
		f(iterator.Key(), iterator.Value())
	}
}

// Map invokes the given function once for each element and returns a container
// containing the values returned by the given function as key/value pairs.
func (m *Map) Map(f func(key1 interface{}, value1 interface{}) (interface{}, interface{})) *Map {
	newMap := &Map{tree: rbt.NewWith(m.tree.Comparator)}
	iterator := m.Iterator()
	for iterator.Next() {
		key2, value2 := f(iterator.Key(), iterator.Value())
		newMap.Put(key2, value2)
	}
	return newMap
}

// Select returns a new container containing all elements for which the given function returns a true value.
func (m *Map) Select(f func(key interface{}, value interface{}) bool) *Map {
	newMap := &Map{tree: rbt.NewWith(m.tree.Comparator)}
	iterator := m.Iterator()
	for iterator.Next() {
		if f(iterator.Key(), iterator.Value()) {
			newMap.Put(iterator.Key(), iterator.Value())
		}
	}
	return newMap
}

// Any passes each element of the container to the given function and
// returns true if the function ever returns true for any element.
func (m *Map) Any(f func(key interface{}, value interface{}) bool) bool {
	iterator := m.Iterator()
	for iterator.Next() {
		if f(iterator.Key(), iterator.Value()) {
			return true
		}
	}
	return false
}

// All passes each element of the container to the given function and
// returns true if the function returns true for all elements.
func (m *Map) All(f func(key interface{}, value interface{}) bool) bool {
	iterator := m.Iterator()
	for iterator.Next() {
		if !f(iterator.Key(), iterator.Value()) {
			return false
		}
	}
	return true
}

// Find passes each element of the container to the given function and returns
// the first (key,value) for which the function is true or nil,nil otherwise if no element
// matches the criteria.
func (m *Map) Find(f func(key interface{}, value interface{}) bool) (interface{}, interface{}) {
	iterator := m.Iterator()
	for iterator.Next() {
		if f(iterator.Key(), iterator.Value()) {
			return iterator.Key(), iterator.Value()
		}
	}
	return nil, nil
}