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• ManagedSpellLease
  • ManagedSpellLease
    • ManagedSpellLease.object
    • ManagedSpellLease.released
    • ManagedSpellLease.release()

ManagedSpellLease

Use md.ManagedSpellLease from the public package namespace.

Implementation source

class ManagedSpellLease(obj: ManagedObjectT, pool: ManagedSpellQuantity)

One object leased from a managed spell's pool, and the one way to hand it back.

Purpose:

Pair a leased object with the pool it came from so it can be given back once - by release() or by leaving a with block - without looking the pool up again. Returned by ReleaseManagedSpell().managed(obj) and, from S5, by Conduit.managed_spell_meld(...).

Contract:

• Holds the object and its pool, both borrowed: the object is the holder's to use until released, the pool is its root store's.

• release() gives the object back once (pool.put_back(obj): the pool's resets, then idle for the next lease); every later call does nothing. The lease counts as released even when the put-back raised - a raising reset (the pool destroyed the object) or a pool torn down with its root (the object stays the holder's) - so nothing is ever given back twice.

• object answers the leased object until the lease is released, then raises: the object went back to its pool and may already be leased again.

• with lease as obj: binds the object; leaving the block releases it, whether or not the block raised, and never suppresses the block's exception. A release error raised while the block was raising propagates with the block's exception as its __context__.

• Identity is not tracked (owner, 2026-10-14): the lease trusts that the object is the one it carries.

Threading:

A handle for one holder, not a thread-safe object: releasing one lease from two threads at once may put the object back twice. Different leases are independent. The pool behind it is thread-safe.

Lifecycle / Cleanup:

The lease owns nothing. Releasing it drops its references to the object and the pool; the released flag stays readable.

Registration:

MELDER KERNEL - guarded. Created by ReleaseManagedSpell.managed (and S5's Conduit.managed_spell_meld); never bound as a spell.

Subsystem Context:

The managed lifetime (EPIC-2026-10-14-managed_spell_quantity): a meld leases an object from its root's pool; ReleaseManagedSpell or a lease gives it back. A class, never a generator, because a generator-based context manager costs about 600 ns more per use (measured 2026-10-14).

AGENT_ACCESS: public

AGENT_PURPOSE:

access: public. One leased managed object and its way back: with ReleaseManagedSpell().managed(obj) as o: releases o on exit (resets run, the object is pooled for the next lease); lease.release() does it by hand, once. Get one from ReleaseManagedSpell().managed(obj).

property object: ManagedObjectT

Return the leased object.

Raises:

RuntimeError -- If the lease was released; its object went back to its pool.

Returns:

The leased object.

Return type:

ManagedObjectT

property released: bool

Return whether the lease has given its object back.

Returns:

True once release() ran (even if the put-back raised).

Return type:

bool

release() → None

Give the object back to its pool, once.

Contract:

• The first call marks the lease released, drops its references and puts the object back (pool.put_back): the pool's resets run in order, then the object is idle for the next lease.

• Every later call returns without doing anything.

Raises:

• RuntimeError -- The pool was torn down with its root; the object is the holder's to dispose.

• Exception -- What a reset raised, after the pool destroyed the object.

• ExceptionGroup -- A raising reset whose disposal failed too, or an elastic trim's disposal failures.

Returns:

None.

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