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Bind functions and instances๏ƒ

๐ŸŸข Beginner ยท Lesson 03

Spells are not only classes - functions and ready-made objects bind with the same verb. RUNTIME LAW (proven by the harness): callable and pre-built spells are always "unique" - the factory runs once and its product is shared; instances are already built.

Before you run๏ƒ

Use the Beginner 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/01_beginner/03_bind_functions_and_instances.py

py -3.14t UX_and_AIX_experiences/01_beginner/03_bind_functions_and_instances.py

Download this collection ยท Source on GitHub

Public surface๏ƒ

function spells, instance spells, string vocabulary

Code๏ƒ

 1"""
 2TIER: beginner (03)
 3GOAL: Spells are not only classes - functions and ready-made objects
 4      bind with the same verb. RUNTIME LAW (proven by the harness):
 5      callable and pre-built spells are always "unique" - the factory
 6      runs once and its product is shared; instances are already built.
 7SURFACE EXERCISED: function spells, instance spells, string vocabulary
 8"""
 9import melder as md
10
11
12def make_settings() -> dict:
13    return {"region": "us-east", "retries": 3}
14
15
16class AlreadyBuilt:
17    def __init__(self, label: str) -> None:
18        self.label = label
19
20
21def main() -> None:
22    book = md.Spellbook()
23    book.bind(spell=make_settings, existence="unique")
24
25    prebuilt = AlreadyBuilt("built-by-hand")
26    book.bind(spell=prebuilt, existence="unique")
27
28    conduit = book.conjure()
29
30    settings = conduit.meld(spell=make_settings)
31    print("function spell melded ->", settings)
32    again = conduit.meld(spell=make_settings)
33    print("unique law: same product back?", settings is again)
34
35    held = conduit.meld(spell=prebuilt)
36    assert held is prebuilt and held.label == "built-by-hand"
37    print("instance spell melded:", held.label)
38
39
40if __name__ == "__main__":
41    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 beginner examples ยท Level guide