Input

# Input and range types (design/input.md). Try: echo 42 | oracle input.zg
MAIN {
    let 'text' := std::input.line[] otherwise "(no input)";     # a boundary: fails with `closed`
    std::print.stored["got: ", 'text', newln];

    # into a range type, the conversion fails on a bad number or an out-of-range one —
    # a failure to handle, never a crash; past it 'n' is provably 0..100
    let 'n' := to.int32[min 0, max 100]['text'] otherwise 50;
    std::print.useful["n = ", 'n', newln];
}