This crate provides procedural macros for generating unique UUIDs associated with tags and types. It offers two main functionalities:

• unique_tag: A procedural macro that generates a unique UUID for a given string tag
• UniqueTypeTag: A derive macro that automatically generates a unique UUID for a type

The generated UUIDs are persisted in a TOML file (types.toml by default) to ensure consistency across multiple compilations and crate boundaries.

Features

• Persistent UUID generation and storage
• Consistent UUID mapping for types and tags
• Thread-safe file handling
• TOML-based storage format

Examples

use unique_uuid_derive::{unique_tag, UniqueTypeTag};

// Using unique_tag macro
let my_tag = unique_tag!("my_custom_tag");

// Using UniqueTypeTag derive macro
#[derive(UniqueTypeTag)]
struct MyStruct;

File Structure

The crate maintains a TOML file with the following structure:

[unique_tags]
"tag_name" = "uuid"

[unique_type_tags]
"type_name" = "uuid"

Implementation Details

• UUIDs are generated using UUID v4 (random)
• File operations are performed with proper error handling
• The system supports both string tags and type tags

Safety

This crate performs file I/O operations during compilation, which may fail if:

• The process lacks file system permissions
• The TOML file becomes corrupted
• Concurrent compilation attempts cause file access conflicts