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Tiny framework for using tuples as first-class citizens in Java.

There is a newer version: 1.1.2

package com.mmnaseri.utils.tuples.facade;

import com.mmnaseri.utils.tuples.FixedTuple;
import com.mmnaseri.utils.tuples.Tuple;

import java.util.function.Function;
import java.util.function.Predicate;
import java.util.function.Supplier;

/**
 * Defines methods that work with the first element of a {@link FixedTuple}.
 *
 * @param  the super-type of the tuple's main data type.
 * @param  the type of the object at the first position.
 * @param  the concrete type of the fixed-size tuple.
 * @author Milad Naseri ([email protected])
 */
public interface HasFirst> extends FixedTuple {

  /** Returns the first element in the current tuple. */
  @SuppressWarnings("unchecked")
  default A first() {
    return (A) get(0);
  }

  /** Sets the first element of the tuple to the indicated value. */
   Tuple first(X value);

  /** Sets the first element of the tuple to the supplied value. */
   Tuple first(Supplier supplier);

  /** Sets the first element of the tuple to the value returned from the function. */
   Tuple first(Function function);

  /** Drops the first element of the tuple, to return a tuple of one size smaller. */
  Tuple dropFirst();

  /** Checks to see if the first element of this tuple matches the given predicate. */
  default boolean checkFirst(Predicate predicate) {
    return predicate.test(first());
  }
}