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Introspect the book๏ƒ

๐ŸŸก Intermediate ยท Lesson 14

The book is inspectable - the spells mapping hands back every registration as SpellIndex -> Spell, the system's two domain nouns, straight off the root namespace.

Before you run๏ƒ

Use the Intermediate guide for prerequisite concepts. Run from a checkout with Melder installed and Python 3.14 free-threading selected. The collection download includes the level's local helper modules.

Run the saved script๏ƒ

python UX_and_AIX_experiences/02_intermediate/14_introspect_the_book.py

py -3.14t UX_and_AIX_experiences/02_intermediate/14_introspect_the_book.py

Download this collection ยท Source on GitHub

Public surface๏ƒ

md.Spellbook.spells, md.SpellIndex, md.Spell

Code๏ƒ

 1"""
 2TIER: intermediate (14)
 3GOAL: The book is inspectable - the spells mapping hands back every
 4      registration as SpellIndex -> Spell, the system's two domain
 5      nouns, straight off the root namespace.
 6SURFACE EXERCISED: md.Spellbook.spells, md.SpellIndex, md.Spell
 7"""
 8import melder as md
 9
10
11class Alpha:
12    pass
13
14
15class Beta:
16    pass
17
18
19def main() -> None:
20    book = md.Spellbook()
21    book.bind(spell=Alpha, existence="unique")
22    book.bind(spell=Beta, existence="many")
23
24    registry = book.spells
25    assert len(registry) >= 2
26    for index, spell in registry.items():
27        assert isinstance(index, md.SpellIndex)
28        assert isinstance(spell, md.Spell)
29    print("book holds", len(registry), "spells, typed as SpellIndex -> Spell")
30
31
32if __name__ == "__main__":
33    main()

Check the outcome๏ƒ

The script contains its own assertions or demonstrated refusal paths. Run it to evaluate those checks against your installed version. The code above is taken directly from the saved file; no run output is invented here.

More intermediate examples ยท Level guide

API contracts๏ƒ