Coproduct3 Example

coproductTesting.kt

fun coproductTesting() {
    val validCoproductA = "1.00".cop<String, Long, Float>().print() //Coproduct3(value=1.00)
    val validCoproductB = 4.00f.cop<Long, String, Float>().print() //Coproduct3(value=4.0)
    val validCoproductC = 9001L.cop<Long, Float, String>().print() //Coproduct3(value=9001)

    val validDuplicateType = "String".cop<String, String, String>().print() //Coproduct3(value=String)

    validCoproductA.select<String>().print() //Some(1.00)
    validCoproductA.select<Long>().print() //None
    validCoproductA.select<Float>().print() //None
    //validCoproductA.select<BigDecimal>() //Doesn't compile

    validCoproductB.select<String>().print() //None
    validCoproductB.select<Long>().print() //None
    validCoproductB.select<Float>().print() //Some(4.0)
    //validCoproductB.select<BigDecimal>() //Doesn't compile

    validCoproductC.select<String>().print() //None
    validCoproductC.select<Long>().print() //Some(9001)
    validCoproductC.select<Float>().print() //None
    //validCoproductC.select<BigDecimal>() //Doesn't compile

    validDuplicateType.select<String>().print() //Some(String)
    //validDuplicateType.select<Unit>() //Doesn't compile

    validCoproductA.value //So we can still pull out the value but it's Any? so it's pretty well useless to do so
    //We can't make it an internal val because we need reified generics for the methods that operate on it

    val foldedBigDecimal = validCoproductA.fold(
            { BigDecimal(it) }, //Actual value
            { BigDecimal(it) },
            { BigDecimal(it.toInt()) }
    ).print() //1.00

//        val foldedBigDecimal = validCoproductA.fold(
//                { BigDecimal(it) },
//                { BigDecimal(it) },
//                { BigDecimal(it) } //Doesn't compile, no constructor for BigDecimal(Float)
//        )

    val mappedCoproductB = validCoproductB.map(
            { "LongValue: $it" },
            { BigDecimal(it) },
            { it * 2 } //Actual value
    ).print() //Coproduct3(value=8.0)

    //Types are preserved from maps returned value
    mappedCoproductB.fold(
            { it },
            { it.abs().toString() },
            { it.dec().toString() }
    ).print() //7.0
}

private fun <T> T.print(): T  {
    System.out.println(this)

    return this
}