import string

fun null_symbol(): symbol {
    var toRet.construct(string::string("$NULL"), false, string::string("$NULL$")): symbol
    return toRet
}

fun symbol(nameIn: *char, terminalIn: bool): symbol {
    var toRet.construct(string::string(nameIn), terminalIn, string::string("no_value")): symbol
    return toRet
}

fun symbol(nameIn: string::string, terminalIn: bool): symbol {
    var toRet.construct(nameIn, terminalIn, string::string("no_value")): symbol
    return toRet
}

fun symbol(nameIn: *char, terminalIn: bool, dataIn: *char): symbol {
    var toRet.construct(string::string(nameIn), terminalIn, string::string(dataIn)): symbol
    return toRet
}

fun symbol(nameIn: string::string, terminalIn: bool, dataIn: string::string): symbol {
    var toRet.construct(nameIn, terminalIn, dataIn): symbol
    return toRet
}

obj symbol (Object) {
    var data: string::string
    var name: string::string
    var terminal: bool

    fun construct(): *symbol {
        data.construct()
        name.construct()
        return this
    }
    fun construct(nameIn: string::string, terminalIn: bool, dataIn: string::string): *symbol {
        name.construct(nameIn)
        terminal = terminalIn
        data.construct(dataIn)
        return this
    }
    fun destruct() {
        data.destruct()
        name.destruct()
    }
    fun copy_construct(old: *symbol) {
        data.copy_construct(&old->data)
        name.copy_construct(&old->name)
        terminal = old->terminal
    }
    fun operator=(old: symbol) {
        destruct()
        copy_construct(&old)
    }
    fun operator==(other: symbol): bool {
        return data == other.data && name == other.name && terminal == other.terminal;
    }
    fun to_string(): string::string {
        var terminalString: *char
        if (terminal)
            terminalString = "true"
        else
            terminalString = "false"
        return name + ": " + data + " " + terminalString
    }
}