In Odin, packages are directories. The system is designed to be straightforward, avoiding the complex dependency nesting found in other languages.

The Golden Rule: One Folder, One Package

• Every .odin file inside a specific folder must belong to the same package (e.g., package bigint).
• All files within that folder share the same scope. You do not need to "include" or "import" files that live in the same directory; they see each other automatically.

Project Structure & Imports

We assume a standard project structure where your root contains your entry point (like main.odin) or your ols.json configuration.

• Local Packages: Any folder inside your project directory is a package.

• Path-Based Importing: To use a local package, you import it using its relative path.

  • If you have /src/math/bigint/, you would use: import "math/bigint".

• Accessing Content: Once imported, you access the package's procedures and data using the package name as a prefix: bigint.add(a, b).

Key Distinctions

• Collections: Names like core:, base:, and vendor: are special "collections" provided by the compiler. These are for libraries that live outside your specific project folder.
• Namespaces: Unlike some languages, the directory name is the "address," but the package declaration inside the file is the "identity" you use in your code.

Pro-tip: If you find yourself overthinking it, remember: If it's in a new folder, it's a new package. If it's in the same folder, it's the same package.