| Equivalent to C's `double` type. | |
| This type will almost always be [`f64`], which is guaranteed to be an [IEEE 754 double-precision float] in Rust. That said, the standard technically only guarantees that it be a floating-point number with at least the precision of a [`float`]; some 16-bit systems use [`f32`], for example. Esoteric systems could use something entirely different from the IEEE-754 standard. | |
| [IEEE 754 double-precision float]: https://en.wikipedia.org/wiki/IEEE_754 | |
| [`float`]: c_float |