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Spellbinder fluent basics๏ƒ

๐ŸŸก Intermediate ยท Lesson 10

The fluent registration hand - SpellBinder reads like a sentence: bind(X).as_unique().named("primary").finalize(). finalize() returns the spell id string and resets the binder for the next registration.

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/10_spellbinder_fluent_basics.py

py -3.14t UX_and_AIX_experiences/02_intermediate/10_spellbinder_fluent_basics.py

Download this collection ยท Source on GitHub

Public surface๏ƒ

md.SpellBinder, md.Spellbook, finalize() -> str

Code๏ƒ

 1"""
 2TIER: intermediate (10)
 3GOAL: The fluent registration hand - SpellBinder reads like a sentence:
 4      bind(X).as_unique().named("primary").finalize(). finalize() returns
 5      the spell id string and resets the binder for the next registration.
 6SURFACE EXERCISED: md.SpellBinder, md.Spellbook, finalize() -> str
 7"""
 8import melder as md
 9
10
11class TelemetrySink:
12    pass
13
14
15class AuditTrail:
16    pass
17
18
19def main() -> None:
20    book = md.Spellbook()
21    binder = md.SpellBinder(book)
22
23    sink_id = binder.bind(TelemetrySink).as_unique().named("sink").finalize()
24    audit_id = binder.bind(AuditTrail).as_many().finalize()
25    assert isinstance(sink_id, str) and isinstance(audit_id, str)
26    print("fluent binds returned spell ids:", sink_id[:8], audit_id[:8])
27
28    conduit = book.conjure()
29    sink_a = conduit.meld(spell=TelemetrySink, binding_name="sink")
30    sink_b = conduit.meld(spell=TelemetrySink, binding_name="sink")
31    audit_a = conduit.meld(spell=AuditTrail)
32    audit_b = conduit.meld(spell=AuditTrail)
33    assert sink_a is sink_b and audit_a is not audit_b
34    print("fluent lifecycles held: unique sink, many audit trails")
35
36
37if __name__ == "__main__":
38    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