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Raku (née Perl 6) has phasers that will be called when exiting a scope. One such idiom is:

    {
        # do stuff
        my $dbh = DB.connect(...);
        # do stuff
        LEAVE .disconnect with $dbh;
        # do stuff
    }
Whenever the scope is left (this could be because of an execution error, or a `return`), the code of the LEAVE phaser will be executed. The `with $dbh` checks whether the $dbh variable contains an instantiated object. If so, it topicalizes (set $_ to it) and calls the disconnect method (`.disconnect` being short for `$_.disconnect`).

For more complex uses, and more tuneable finalizing, there is the `FINALIZER` module in the ecosystem: https://modules.raku.org/dist/FINALIZER






Sure, but "schedule action at scope exit" is an easy (assuming your runtime already knows how to unwind the stacks) problem to solve. "Perform escape analysis and guarantee immediate destruction; efficiently without full gc nor refcounting" is not and they're not the same problem at all.



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