The example code is supposed to fail to compile, but if it does run it
panics. This somehow confuses the compiler so that either the
compile_fail tag compiles but causes a lint warning about the panic or
using should_panic fails to compile.
Change the tag to ignore
The function name in the example is the std function not this crates.
There is also an unused variable.
Correct the name of the function and prefix the unused vairable with an
underscore.
Previously we've used `try_into().expect()` because const generics were
unavailable. Then they became available but we didn't realize we could
already convert a bunch of code to not use panicking conversions. But we
can (and could for a while).
This adds an extension trait for arrays to provide basic non-panicking
operations returning arrays, so they can be composed with other
functions accepting arrays without any conversions. It also refactors a
bunch of code to use the non-panicking constructs but it's certainly not
all of it. That could be done later. This just aims at removing the
ugliest offenders and demonstrate the usefulness of this approach.
Aside from this, to avoid a bunch of duplicated work, this refactors
BIP32 key parsing to use a common method where xpub and xpriv are
encoded the same. Not doing this already led to a mistake where xpriv
implemented some additional checks that were missing in xpub. Thus this
change also indirectly fixes that bug.
In the past we've been using `chunks_exact` because const generics were
unstable but then, when they were stabilized we didn't use `as_chunks`
(or `array_chunks`) since they were unstable. But the instability was
only because Rust devs don't know how to handle `0` being passed in. The
function is perfectly implementable on stable. (With a tiny,
easy-to-understand `unsafe` block.) `core` doesn't want to make a
decision for all other crates yet but we can make it for our own crates
because we know that we simply never pass zero. (And even if we did, we
could just change the decision.)
It also turns out there's a hack to simulate `const {}` block in our
MSRV, so we can make compilation fail early.
This commit adds an extension trait to internals to provide the methods,
so we no longer have to use `chunks_exact`. It also cleans up the code
quite nicely.
Jamil Lambert, PhD
Fmt Bot
Martin Habovstiak