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• Observe registration and runtime lifecycles
  • Pick the boundary you need
  • Keep the result separate from the observation
  • The workflow in code
  • Runnable examples

Observe registration and runtime lifecycles

Prerequisite: configuration. Hooks attach observation to a book or registration so call sites can keep using ordinary meld and lifecycle verbs.

Pick the boundary you need

Boundary	Registration surface	Saved demonstration
Spell creation	SpellBinder.with_pre_hook, with_activation_hook, with_post_hook	Record construction events
Meld	configuration.add_hook(book.id, name, callback)	Observe pre/post resolution
Conduit	The same book-keyed hook registration	Observe creation and cleanup
Links and contracts	The same book-keyed hook registration	Observe linking, pull, and sever

The book ID matters when a configuration serves several books. Register the callbacks before the lifecycle operation you intend to observe. The runnable examples collect events in memory so you can inspect what actually fired.

Keep the result separate from the observation

A hook records a moment in a lifecycle. The meld still supplies the resolved object. Use the meld-hook lesson's repeated resolutions and event counts as a small working pattern; use the conduit lesson when cleanup observation matters.

For the dynamic arc, read linking before the link-hook lesson. The latter observes the same owner/borrower operations; it adds no alternative sharing procedure.

The workflow in code

These are the core steps from the saved example. Use its complete linked script for all class definitions and setup.

def main() -> None:
    events = []

    book = md.Spellbook()
    config = book.get_configuration()
    config.add_hook(book.id, "on_meld_pre_resolve",
                    lambda *a, **k: events.append("pre"))
    config.add_hook(book.id, "on_meld_post_resolve",
                    lambda *a, **k: events.append("post"))

    book.bind(spell=Watched, existence="many")
    conduit = book.conjure()

    conduit.meld(spell=Watched)
    conduit.meld(spell=Watched)
    print("meld pipeline observed:", events)
    assert events.count("pre") >= 2 and events.count("post") >= 2
    print("every meld fired pre and post - the pipeline is watchable")

Runnable examples

• Config meld hooks — Intermediate 32

• Registration hooks — Intermediate 03

• Config conduit lifecycle hooks — Intermediate 33

• Config link and contract hooks — Intermediate 34

All intermediate examples · Level contents · Full contents

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