Hallo !

The problem of automatic object garbage collection was itching me for some time now. So I did spend some time and here is the solution.

The basic idea is to auto-destroy objects created within a procedure when the procedure goes out of context. I would like to hear some comments from Uwe/Gustaf and/or other experienced XOTcl'ers. Similar might even be included in 1.0 if people need such thing. I definitely do.

The below depends on the array "__gc" created in the calling's procedure context, one class proc "__gc" and one new costructor, "volatile" as shown below.

Attached is a piece of test-code to verify the operation.

Cheer's Zoran

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# # Gets invoked from variable unset callbacks. # Class proc __gc {n1 n2 op} { set l [::expr {[::info level] > 0}] if {![::uplevel $l ::info exists __gc($n1)]} { ::incr l } ::uplevel $l $__gc($n1) destroy }

# # Used to instantiate "volatile" objects. # These get auto-destroyed when the procedure goes out of context. # Class instproc volatile {n args} { ::upvar $n v ::trace variable v u [list Class __gc] ::set v [[self] autoname -instance [self]] ::uplevel [::expr {[::info level]<2?1:2}] ::set __gc($n) $v ::eval [self] create $v $args }

# # Test routines # proc aa {} { _foo_ volatile obj $obj test bb } proc bb {} { _foo_ volatile obj $obj test cc } proc cc {} { _foo_ volatile obj $obj test unset obj dd } proc dd {} { _foo_ volatile obj $obj test } proc gctest {} { Class _foo_ _foo_ instproc test {} {puts stderr [self]} set cmds [info comm _foo_*] aa if {[info comm _foo_*] == $cmds} { puts stderr ok } else { puts stderr fail } }

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