A pattern matching library for Java 8. Motif provides scala-like pattern matching in Java 8.
IntStream.range(0, 101).forEach(
n -> System.out.println(
match(Tuple2.of(n % 3, n % 5))
.when(tuple2(eq(0), eq(0))).get(() -> "FizzBuzz")
.when(tuple2(eq(0), any())).get(y -> "Fizz")
.when(tuple2(any(), eq(0))).get(x -> "Buzz")
.orElse(String.valueOf(n))
.getMatch()
)
);
Optional<Person> personOpt = getPerson();
match(personOpt)
.when(some(any())).then(person -> doStuff(person))
.when(none()).then(() -> System.out.println("Person not found"))
.doMatch();
public long factorial(long i) {
return match(i)
.when(eq(0)).get(() -> 1l)
.when(any()).get(x -> x * factorial(x - 1))
.getMatch();
}
Optional<Tuple2<String, String>> opt = Optional.of(Tuple2.of("first", "second"));
match(opt)
.when(some(tuple2(eq("third"), any()))).then(b -> doStuff(b))
.when(some(tuple2(any(), eq("second")))).then(a -> doStuff(a))
.when(none()).then(() -> System.out.println("Tuple not found"))
.doMatch();
List<String> list = Arrays.asList("a", "b", "c", "d");
match(list)
.when(nil()).then(() -> System.out.println("Empty List"))
.when(headNil(eq("b"))).then(() -> System.out.println("Singleton List of 'b'"))
.when(headNil(any())).then(head -> System.out.println("Singleton List of " + head))
.when(headTail(any(), any())).then(
(head, tail) -> System.out.println("head: " + head + " Remaining: " + tail))
.doMatch();
Add the Sonatype snapshot repository:
<repository>
<id>ossrh</id>
<name>Sonatype OSSRH</name>
<url>https://oss.sonatype.org/content/repositories/snapshots/</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
Download the latest snapshot JAR via Maven:
<dependency>
<groupId>com.leacox.motif</groupId>
<artifactId>motif</artifactId>
<version>1.0-SNAPSHOT</version>
</dependency>
Copyright 2015 John Leacox
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
https://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.