(Firstly, I changed `n` to `b`, as that is less confusing. It's not a length, it's a right boundary.)
The invariant maintained is `cur < b`. In the worst case `2*cur + 1` results in a maximum of `2b`. Since `2b` is not guaranteed to be lower than `maxInt`, we have to add one overflow check to `siftDown` to make sure we avoid undefined behavior.
LLVM also seems to have a nicer time compiling this version of the function. It is about 2x faster in my tests (I think LLVM was stumped by the `child += @intFromBool` line), and adding/removing the overflow check has a negligible performance difference on my machine. Of course, we could check `2b <= maxInt` in the parent function, and dispatch to a version of the function without the overflow check in the common case, but that probably is not worth the code size just to eliminate a single instruction.
Forcing the key to be of the same type as the sorted items used during
the search is a valid use case.
There, however, exists some cases where the key and the items are of
heterogeneous types, like searching for a code point in ordered ranges
of code points:
```zig
const CodePoint = u21;
const CodePointRange = [2]CodePoint;
const valid_ranges = &[_]CodePointRange{
// an ordered array of ranges
};
fn orderCodePointAndRange(
context: void,
code_point: CodePoint,
range: CodePointRange
) std.math.Order {
_ = context;
if (code_point < range[0]) {
return .lt;
}
if (code_point > range[1]) {
return .gt;
}
return .eq;
}
fn isValidCodePoint(code_point: CodePoint) bool {
return std.sort.binarySearch(
CodePointRange,
code_point,
valid_ranges,
void,
orderCodePointAndRange
) != null;
}
```
It is so expected that `std.sort.binarySearch` should therefore support
both homogeneous and heterogeneous keys.
This also adds `std.sort.sortContext` and
`std.sort.insertionSortContext` which are more advanced methods that
allow overriding the `swap` method. The former calls the latter for now
because reworking the main sort implementation is a big task that can be
done later without any changes to the API.
These changes have been made to resolve issue #10037. The `Random`
interface was implemented in such a way that causes significant slowdown
when calling the `fill` function of the rng used.
The `Random` interface is no longer stored in a field of the rng, and is
instead returned by the child function `random()` of the rng. This
avoids the performance issues caused by the interface.
We already have a LICENSE file that covers the Zig Standard Library. We
no longer need to remind everyone that the license is MIT in every single
file.
Previously this was introduced to clarify the situation for a fork of
Zig that made Zig's LICENSE file harder to find, and replaced it with
their own license that required annual payments to their company.
However that fork now appears to be dead. So there is no need to
reinforce the copyright notice in every single file.
Conflicts:
* doc/langref.html.in
* lib/std/enums.zig
* lib/std/fmt.zig
* lib/std/hash/auto_hash.zig
* lib/std/math.zig
* lib/std/mem.zig
* lib/std/meta.zig
* test/behavior/alignof.zig
* test/behavior/bitcast.zig
* test/behavior/bugs/1421.zig
* test/behavior/cast.zig
* test/behavior/ptrcast.zig
* test/behavior/type_info.zig
* test/behavior/vector.zig
Master branch added `try` to a bunch of testing function calls, and some
lines also had changed how to refer to the native architecture and other
`@import("builtin")` stuff.
* Implements #3768. This is a sweeping breaking change that requires
many (trivial) edits to Zig source code. Array values no longer
coerced to slices; however one may use `&` to obtain a reference to
an array value, which may then be coerced to a slice.
* Adds `IrInstruction::dump`, for debugging purposes. It's useful to
call to inspect the instruction when debugging Zig IR.
* Fixes bugs with result location semantics. See the new behavior test
cases, and compile error test cases.
* Fixes bugs with `@typeInfo` not properly resolving const values.
* Behavior tests are passing but std lib tests are not yet. There
is more work to do before merging this branch.
yujiri8