feat: add `number/float16/ctor`

[gururaj1512]

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Resolves None.

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• feat: add number/float16/ctor

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Coverage Report

Package	Statements	Branches	Functions	Lines
number/float16/ctor	$\color{green}331/331$ $\color{green}+0.00%$	$\color{green}13/13$ $\color{green}+0.00%$	$\color{green}4/4$ $\color{green}+0.00%$	$\color{green}331/331$ $\color{green}+0.00%$

The above coverage report was generated for the changes in this PR.

[gururaj1512]

So this package should just contain

typedef struct {
	uint16_t bits;
} stdlib_float16_t;

If that's the case I think we would not need the addon to test as discussed.

[kgryte]

No, it should contain more. It was that you had included a subset of functions for which we have public APIs which exist elsewhere. Certainly most of the "from" APIs should remain in this package.

[gururaj1512]

The "from" APIs are internally using the stdlib_float16_from_float32 and that API if created in different package would require number/float16/ctor. This is creating deadlock.

[kgryte]

Ah, right, circular native dependencies. 🤦‍♂️ You're right. This is a pickle. It is either all or none. Yeah, maybe it is the case that this package only includes the stdlib_float16_t type definition. Otherwise, all conversion utils exist outside this package in various micro-modules.

[kgryte]

...otherwise, it is odd if JS conversion utils exist outside this package, but C conversion functions don't. Better to be consistent and co-localize JS/C functions. While it departs from complex128 and complex64, it is okay for those to be special. We'll likely need to do the same thing as float16 when we add int64 and uint64 value types.

[gururaj1512]

/stdlib update-copyright-years

[gururaj1512]

LGTM after refactoring. In particular, I went ahead and added small helper utilities for portably converting between an opaque float16 value and its binary representation, with support for native float16 support when available.

This means that the C implementation of to-word and from-word can be very thin wrappers around these helpers and we can avoid some of the hairy implementation details we needed to implement in JS.

Yeah, I see this way it makes much more sense and easier.