The brain float

# The brain float (owner, 2026-10-02): `brain16`. bin32's range in 16 bits,
# with 7 bits of precision; its own family; each operation rounds to the nearest brain16.
MAIN {
    let 'a': brain16 = 0.1;                     # a literal rounds to the nearest: 0.10009765625
    let 'b': brain16 = 0.2;
    let 'c': brain16 = 'a' plus 'b';
    std::print.stored['a', " ", 'c', newln];       # what is stored
    std::print.useful['a', " ", 'c', newln];  # the shortest text that rounds back to it
    let 'x': bin64 = 300.7;
    let 'w' := to.brain16['x'];                 # into it rounds: 300 (7 bits)
    let 'back' := to.bin32['w'];                # out of it into a bin32 is exact
    let 'n' := to.int32['w'] otherwise -1;      # whole, so it converts
    std::print.useful['w', " ", 'back', " ", 'n', newln];
    let 'xs': list[brain16] = [0.5, 1.5, 2.5];
    std::print.format["{} {:.2} {:?}\n", 'xs', 'a', 'a'];
}