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Converters and Comprehenders for FunctionalJava

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package com.aol.cyclops.functionaljava.comprehenders;

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

import com.aol.cyclops.types.extensability.Comprehender;
import com.aol.cyclops.types.extensability.ValueComprehender;

import fj.data.Either;
import fj.data.Either.LeftProjection;
import fj.data.Option;

public class LeftProjectionComprehender implements ValueComprehender {

    @Override
    public Object filter(LeftProjection t, Predicate p) {
        return t.filter(x -> p.test(x));
    }

    @Override
    public Object map(LeftProjection t, Function fn) {
        return t.map(x -> fn.apply(x));
    }

    @Override
    public Object flatMap(LeftProjection t, Function fn) {
        return t.bind(x -> fn.apply(x));
    }

    @Override
    public LeftProjection of(Object o) {
        return Either.left(o)
                     .left();
    }

    @Override
    public LeftProjection empty() {
        return Either.left(Option.none())
                     .left();
    }

    @Override
    public Class getTargetClass() {
        return LeftProjection.class;
    }

    public Object resolveForCrossTypeFlatMap(Comprehender comp, LeftProjection apply) {
        Option present = apply.toOption();
        if (present.isSome())
            return comp.of(present.some());
        else
            return comp.empty();

    }

}