diff options
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 30 |
1 files changed, 24 insertions, 6 deletions
@@ -66814,9 +66814,17 @@ A finalizer is itself permitted to call .code finalize to register the original .code object -or any other object for finalization. Such registrations made during -finalization execution are not eligible for the current phase of finalization -processing; they will be processed in a later garbage collection pass. +or any other object for finalization. Finalization processing can be +understood as taking place in one or more rounds. At the start of each round, +finalizers are identified that are to be called, arranged in order, and removed +from the registration list. If this identification stage produces no +finalizers, then finalization ends. Otherwise, those finalizers are processed, +and then another round is initiated, to look for finalizers that may have been +registered during the previous round. + +Note: it is possible for the application to create an infinite finalization +loop, if one or more objects have finalizers that register new finalizers, +which register new finalizers and so on. .coNP Function @ call-finalizers .synb @@ -66832,12 +66840,22 @@ If any finalizers are called, it returns otherwise .codn nil . +Finalization performed by +.code call-finalizers +works in the manner described under the specification of he +.code finalize +function. + It is permissible for a finalizer function itself to call .codn call-finalizers . -Such a call can happen in two possible contexts: during actual -reclamation driven by garbage collection, or under the scope of a +Such a call can happen in two possible contexts: finalization +initiated by by garbage collection, or under the scope of a .code call-finalizers -invocation from application code. +invocation from application code. Doing so is safe, since the finalization +logic may be re-entered recursively. When finalizers are being called during a +round of processing, those finalizers have already been removed from the +registration list, and will not be redundantly invoked by a recursive +invocation of finalization. Under the scope of garbage-collection-driven reclamation, the order of finalizer calls may not be what the application logic |