Add uuid! macro to produce compile-time Uuids from strings.

[mehcode]

I'm submitting a(n) feature|refactor

Description

This moves out parsing into its own crate, uuid-parser; and, adds a third crate, uuid-macros, with a single expression proc-macro uuid! that can produce compile-time UUIDs from strings.

As this is a pretty invasive refactor, please let me know if there are changes to the organization you'd like me to make.

Motivation

Replaces:

let id = Uuid::parse_str("550e8400-e29b-41d4-a716-446655440000").unwrap();

With:

let id = uuid!("550e8400-e29b-41d4-a716-446655440000");

Furthermore, after #394, this enables const UUIDs to be const themselves.

const ID: Uuid = uuid!("550e8400-e29b-41d4-a716-446655440000");

Tests

A new test was added to showcase uuid! and prove it works.

Related Issue(s)

[todo]

explain multiple segment count.

Parsers can expect a range of Uuid segment count.

---

uuid/uuid-parser/src/lib.rs

Lines 57 to 62 in 1a4d28c

	// TODO: explain multiple segment count.
	// BODY: Parsers can expect a range of Uuid segment count.
	// This needs to be expanded on.
	expected: Expected,
	/// The number of segments found.
	found: usize,

---

This comment was generated by todo based on a TODO comment in 1a4d28c in #395. cc @mehcode.

[todo]

explain multiple lengths.

Parsers can expect a range of Uuid lenghts.

---

uuid/uuid-parser/src/lib.rs

Lines 80 to 85 in 1a4d28c

	// TODO: explain multiple lengths.
	// BODY: Parsers can expect a range of Uuid lenghts.
	// This needs to be expanded on.
	expected: Expected,
	/// The invalid length found.
	found: usize,

---

This comment was generated by todo based on a TODO comment in 1a4d28c in #395. cc @mehcode.

[todo]

remove the u8 cast

this only needed until we switch to

---

uuid/uuid-parser/src/lib.rs

Lines 192 to 197 in 1a4d28c

	// TODO: remove the u8 cast
	// BODY: this only needed until we switch to
	// ParseError
	if ACC_GROUP_LENS[group] as u8 != digit {
	// Calculate how many digits this group consists of
	// in the input.

---

This comment was generated by todo based on a TODO comment in 1a4d28c in #395. cc @mehcode.

[todo]

remove the u8 cast

this only needed until we switch to

---

uuid/uuid-parser/src/lib.rs

Lines 199 to 204 in 1a4d28c

	// TODO: remove the u8 cast
	// BODY: this only needed until we switch to
	// ParseError
	digit - ACC_GROUP_LENS[group - 1] as u8
	} else {
	digit

---

This comment was generated by todo based on a TODO comment in 1a4d28c in #395. cc @mehcode.

[todo]

remove the u8 cast

this only needed until we switch to

---

uuid/uuid-parser/src/lib.rs

Lines 240 to 245 in 1a4d28c

	// TODO: remove the u8 cast
	// BODY: this only needed until we switch to
	// ParseError
	digit - ACC_GROUP_LENS[group - 1] as u8
	} else {
	digit

---

This comment was generated by todo based on a TODO comment in 1a4d28c in #395. cc @mehcode.

[todo]

remove the u8 cast

this only needed until we switch to

---

uuid/uuid-parser/src/lib.rs

Lines 270 to 275 in 1a4d28c

	// TODO: remove the u8 cast
	// BODY: this only needed until we switch to
	// ParseError
	if ACC_GROUP_LENS[4] as u8 != digit {
	return Err(ParseError::InvalidGroupLength {
	expected: Expected::Exact(GROUP_LENS[4]),

---

This comment was generated by todo based on a TODO comment in 1a4d28c in #395. cc @mehcode.

[kinggoesgaming]

Thanks for this PR. However I am not yet comfortable with including this into the main crate. However we have an inactive crate (uuid-rs/uuid_macro) which was designed for this for this purpose (polish it out and then introduced). I would love if you open this again that.

And post that I think it would be a good point to publish that crate aswell

[mehcode]

That crate looks similar enough. I hadn't noticed it. Though I don't see how I could improve the crate much (from a quick glance) without the split here to move out uuid-parser.

I'd recommend renaming it to uuid-macros though. Never know when we might want a second one.