RosettaCodeData/Task/Menu/Langur/menu.langur

val choose = fn*(entries list) {
    if not entries: return ""

    # print the menu
    writeln join(map(entries, 1..len(entries), by=fn(e, i) { "{{i:2}}: {{e}}" }), delim="\n")

    val idx = read(
        prompt="Select entry #: ",
        validation=fn(x) {
            if not x -> RE/^[0-9]+$/: return false
            val y = x -> number
            y > 0 and y <= len(entries)
        },
        errmsg="invalid selection\n",
        maxattempts=-1,
    ) -> number

    entries[idx]
}

writeln choose(["fee fie", "eat pi", "huff and puff", "tick tock"])