org.organicdesign.fp.collections.ImSet Maven / Gradle / Ivy
// Copyright 2015-04-13 PlanBase Inc. & Glen Peterson
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package org.organicdesign.fp.collections;
/** An immutable set interface */
public interface ImSet extends UnmodSet {
/** Adds an item, returning a modified version of the set (leaving the original set unchanged). */
ImSet put(E e);
/** Removes the given item, returning a modified version of the set (leaving the original set unchanged). */
ImSet without(E key);
// /**
// A sequence of the items contained in this set. Note that for some implementations, multiple calls to seq()
// will yield sequences with different ordering of the same elements.
// */
// Sequence seq();
default ImSet union(Iterable iter) {
ImSet ret = this;
for (E e : iter) { ret = ret.put(e); }
return ret;
}
/** {@inheritDoc} */
@Override UnmodIterator iterator();
/**
* This method goes against Josh Bloch's Item 25: "Prefer Lists to Arrays", but is provided for backwards
* compatibility in some performance-critical situations. If you really need an array, consider using the somewhat
* type-safe version of this method instead, but read the caveats first.
* {@inheritDoc}
*/
@Override default Object[] toArray() { return UnmodCollection.toArray(this); }
}