README.md

8. Modules

Modules split Pilang programs into reusable files and libraries. A module can be a user-written .pi file or a built-in module provided by the runtime.

Importing a module loads it once, caches it, and exposes its public symbols through a module object or through selected local names.

Key Ideas

• import math loads a module and binds it to a name.
• import math, random imports multiple modules with one import keyword.
• import math.{floor, ceil} imports selected exports.
• import math.{floor:f} imports an export with an alias.
• import math:mt.{cos, sin} imports math as mt and selected exports.
• import math.* imports all public exports into the current module/global scope.
• Top-level names in a user module are exported automatically.
• Names beginning with _ are private and cannot be imported from outside.

Imported module objects expose metadata fields such as name, path, is_main, and exports.

Sections

• 8.1 Importing Modules
• 8.2 Exporting Symbols
• 8.3 Module Paths
• 8.4 Built-in Modules
• 8.5 User Modules