There was a question whether this is equally performant. There are
multiple good reasons why it should be:
1. `get_or_insert_with` is marked `#[inline]`
2. Any good optimizer will inline a function that is used exactly once
3. 1 and 2 conclude that the closure will get inlined
4. Computing self.tx can then be moved to the only branch where it is
required.
5. Even if get_or_insert_with didn't get optimized, which is extremely
unlikely, the `tx` field is at the beginning of the struct and it
probably has pointer alignment (`Deref` suggests it's a pointer).
Alignment larger than pointer is not used, so we can expect the
fields to be ordered as-defined. (This is not guaranteed by Rust but
there's not good reason to change the order in this case.) We can
assume that offset to tx is zero in most cases which means no
computation is actually needed so the expression before closure is
no-op short of passing it into the closure as an argument.
At the time of writing `#[inline]` can be seen at
https://doc.rust-lang.org/src/core/option.rs.html#933
Based on the original work by Justin Moon.
*MSRV unchanged from 1.29.0.*
When `std` is off, `no-std` must be on, and we use the [`alloc`](https://doc.rust-lang.org/alloc/) and core2 crates. The `alloc` crate requires the user define a global allocator.
* Import from `core` and `alloc` instead of `std`
* `alloc` only used if `no-std` is on
* Create `std` feature
* Create `no-std` feature which adds a core2 dependency to polyfill `std::io` features. This is an experimental feature and should be
used with caution.
* CI runs tests `no-std`
* MSRV for `no-std` is 1.51 or so
Fixes#608. In #567 the Display impl for ChildNumber was
consciously changed, assuming the semver break would not
affect any correctly implemented downstream projects. We
were wrong.
It's very useful to Bitcoin applications, and especially "L2" ones, to
effectively compute feerates. Currently (and this is very unlikely to
change) bitcoind nodes compute the virtual size as a rounded-up division
of the size in witness units by 4, with a penalty for transactions that
are essentially >5% full of sigops.
Signed-off-by: Antoine Poinsot <darosior@protonmail.com>
This introduces some constants defined by Bitcoin Core which as a
consequence define some network rules in a new 'policy' module.
Only some were picked, which are very unlikely to change. Nonetheless a
Warning has been put in the module documentation.
Script-level constants are left into rust-miniscript where they are
already defined (src/miniscript/limits.rs).
Martin Habovstiak
Riccardo Casatta
Andrew Poelstra
Devrandom
Sebastian
Dr Maxim Orlovsky
Matt Corallo
Sebastian Geisler
Alekos Filini
Roman Zeyde
Antoine Poinsot