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Built-in & Standard Library

This part of the guide is reference material.

Acton has two closely related pieces here:

  • built-in definitions that are always available, such as core types and built-in protocols
  • standard library modules that you import explicitly, such as math and re

Built-in names are part of the language environment. Standard library modules are brought into scope with import.

Use Built-in protocols for the protocols defined in __builtin__, including Eq, Ord, Hashable, Iterable, and Mapping.

This split matches the implementation structure as well: built-in protocols and core types live in __builtin__, while module APIs such as math live in separate standard library modules.

Use Standard Library for imported modules.