kraken/tests/test_adt.krak

import io:*

adt options {
    option0,
    option1
}

adt maybe_int {
    no_int,
    an_int: int
}

fun handle_possibility(it: maybe_int) {
    if (it == maybe_int::no_int()) {
        println("no int")
    }
    /*if (it == maybe_int::an_int) {*/
    else {
        print("an int: ")
        println(it.an_int)
    }
}

fun give_maybe(give_it: bool): maybe_int {
    if (give_it)
        return maybe_int::an_int(7)
    return maybe_int::no_int()
}

fun can_pass(it: options): options {
    return it
}

fun main():int {
    var it: options = can_pass(options::option0())
    if (it == options::option0()) {
        println("nope")
    }
    if (it == options::option1()) {
        println("option1")
    }

    var possibility = give_maybe(false)
    handle_possibility(possibility)
    possibility = give_maybe(true)
    handle_possibility(possibility)
    if ( maybe_int::an_int(7) == maybe_int::an_int(7) )
        println("equality true works!")
    else
        println("equality true fails!")
        
    if ( maybe_int::an_int(7) != maybe_int::an_int(8) )
        println("equality false works!")
    else
        println("equality false fails!")

    match (maybe_int::an_int(11)) {
        maybe_int::an_int(the_int) {
            print("matched an int:")
            print(the_int)
            println(" correctly!")
        }
        maybe_int::no_int() {
            println("matched no int incorrectly!")
        }
    }
    match (maybe_int::no_int()) {
        maybe_int::an_int(the_int) println("matched an int incorrectly!")
        maybe_int::no_int() println("matched no int correctly!")
    }
    return 0
}