pub fn float_repr(f: f64, out: &mut String)Expand description
Python’s repr(float): the shortest digits that round trip, in fixed notation when the decimal
exponent is from -4 to 15 and in scientific notation otherwise, with a sign and at least two
exponent digits. Integral values keep a .0.
§Panics
Never. The expects below hold for every string Rust’s {:e} writes.