com.github.tonivade.purefun.instances.TupleInstances Maven / Gradle / Ivy

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/*
 * Copyright (c) 2018-2019, Antonio Gabriel Muñoz Conejo 
 * Distributed under the terms of the MIT License
 */
package com.github.tonivade.purefun.instances;

import com.github.tonivade.purefun.Function1;
import com.github.tonivade.purefun.Higher1;
import com.github.tonivade.purefun.Higher2;
import com.github.tonivade.purefun.Instance;
import com.github.tonivade.purefun.Tuple1;
import com.github.tonivade.purefun.Tuple2;
import com.github.tonivade.purefun.typeclasses.Bifunctor;
import com.github.tonivade.purefun.typeclasses.Functor;

public interface TupleInstances {

  static Functor functor() {
    return new Tuple1Functor() {};
  }

  static Bifunctor bifunctor() {
    return new Tuple2Bifunctor() {};
  }
}

@Instance
interface Tuple1Functor extends Functor {

  @Override
  default  Tuple1 map(Higher1 value, Function1 map) {
    return value.fix1(Tuple1::narrowK).map(map);
  }
}

@Instance
interface Tuple2Bifunctor extends Bifunctor {

  @Override
  default  Tuple2 bimap(Higher2 value,
                                          Function1 leftMap,
                                          Function1 rightMap) {
    return value.fix2(Tuple2::narrowK).map(leftMap, rightMap);
  }
}