Previously, the `rand` and `rustc-serialize` dependencies were optional
except they were required for the `bigint` feature.
Make the dependency on the `rand` crate optional in all cases.
including when the `bigint` feature is selected. Some of the tests for
the bigint feature are randomized so, while `rand` is now an optional
dependency, it is a non-optional dev-dependency.
Similarly, make the dependency on the `rustc-serialize` crate optional
in all cases, including when the `bigint` feature is selected.
We can save a multiplication if we start the accumulation basically at
the first set bit of the exponent, rather than starting at one and
waiting to multiply. We only need one itself if the exponent is zero,
which is easy to pre-check.
Before:
test pow_bench ... bench: 8,267,370 ns/iter (+/- 93,319)
After:
test pow_bench ... bench: 7,506,463 ns/iter (+/- 116,311)
The hidden "mod test" layout of the first example has been broken for a
while, but it wasn't noticed because rustdoc wasn't passing any features
at all. That was fixed in rust-lang/rust#30372, and now we need to get
our ducks in a row too.
Making bignum optional allows skipping the rustc-serialize and rand
dependencies too, and it makes a big difference in num's build time.
With default (all) features, clean build time including dependencies: 27
seconds.
With no default features, clean build time including dependencies (none):
5 seconds.
Along the way, this commit also rationalizes the traits a bit more.
Moving to stable required vendoring a couple of minor things (notably,
radix formatting).
The code was performing an extra squaring of the base, which might
trigger an arithmetic overflow that doesn't matter to the result. Now
this squaring is only attempted when enough exp remains to need it.
A new doctest tries pow(6u8, 3), where an extra square would exceed 256.
Now, arithmetic binary operator traits take operands by value,
but non-copyable types such as `BigUint` should not always moved out when
applying operators.
This commit implements these operators not only for bare structs also
these references.
By-value implementations are forwarded to by-reference implementations
for now. In the future, by-value implementations may be replaced with
more efficient implementations (for example, the implementation that
reuses moved buffers.)
mathematcs.
Import numeric traits and functions that were removed from the standard library.
This also implements `AdditiveIterator` and `MultiplicativeIterator` for
`BigUint` and `BigInt`.
closes#28
Josh Stone
est31
Brian Smith
root
Oliver Mader
Alex Crichton
kennytm
Aaron Turon
Huon Wilson
Matt Brubeck
Josh Stone
Austin Bonander
Sam Payson
gifnksm
Sven Nilsen
Steve Klabnik