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Rename Perl 6 -> Raku, alphabetize, minor clean-up
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Thundergnat (talk | contribs) (Rename Perl 6 -> Raku, alphabetize, minor clean-up) |
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=={{header|Java}}==
The situation for Java is as described below in the entry for its sister JVM language, Kotlin.
=={{header|Julia}}==
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Perl uses reference counting as its method of managing memory use. As soon as the last reference to a value is released, the value may be destroyed and freed, and handed back to the memory pool. However the exact timing of this action is not under programmer control.
Within your program, by using <code>undef</code> and <code>delete</code>, you can <i>hint</i> to Perl that it would now be OK to release this memory. Most importantly, such actions should not be confused with releasing memory back to the operating system. In cases where it is necessary to temporarily allocate a large amount of memory, do so via <code>fork</code>, so when the child process exits the memory is truly freed back to the system.
=={{header|Perl 6}}==▼
In general, there is no specific mechanism to do a timely destruction of an object, be it code, data, variables, whatever. Perl 6 does automatic garbage collection on objects that are no longer being used. Unlike previous version of Perl, Perl 6 doesn't use reference counting to track when memory may be garbage collected as that tends to be very difficult to get correct and performant in multi-threaded applications. Rather it performs a "reachability analysis" to determine when objects can be evicted from memory and safely removed. ▼
Perl 6 objects can provide a "DESTROY" method, but you cannot be sure when (if ever) it will be called. Perl 6 tends to not be very memory frugal. If there is lots of memory to be had, it will cheerfully use lots of it. It gets more aggressive about conserving if memory is tight, but usually will trade memory for performance. If and when garbage collection ''has'' run, the freed memory is then available to to the general OS pool for any process to claim. ▼
There are some specific details that will allow some finer control of garbage collection in special circumstances, but the average Perl 6 programmer will not need to know about or deal with them.▼
=={{header|Phix}}==
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=={{header|Python}}==
The [https://docs.python.org/3.4/reference/simple_stmts.html?highlight=del#grammar-token-del_stmt del] statement can make objects (both code and data), available for reuse.
Racket has a JIT compiler that translates functions to machine code whenever they are applied. When such a function is garbage-collected, the JITted machine code is released or re-used with it. Therefore, to reclaim some executable code segment, simply drop references to the function.▼
(formerly Perl 6)
▲In general, there is no specific mechanism to do a timely destruction of an object, be it code, data, variables, whatever. Perl 6 does automatic garbage collection on objects that are no longer being used. Unlike previous version of Perl, Perl 6 doesn't use reference counting to track when memory may be garbage collected as that tends to be very difficult to get correct and performant in multi-threaded applications. Rather it performs a "reachability analysis" to determine when objects can be evicted from memory and safely removed.
▲Perl 6 objects can provide a "DESTROY" method, but you cannot be sure when (if ever) it will be called. Perl 6 tends to not be very memory frugal. If there is lots of memory to be had, it will cheerfully use lots of it. It gets more aggressive about conserving if memory is tight, but usually will trade memory for performance. If and when garbage collection ''has'' run, the freed memory is then available to to the general OS pool for any process to claim.
▲There are some specific details that will allow some finer control of garbage collection in special circumstances, but the average Perl 6 programmer will not need to know about or deal with them.
When using REXX in the (VM) CMS environment, the use of '''NUCXDROP''' can be used to release memory (virtual storage) that a REXX program is using (when previously loaded into virtual memory via '''NUCXLOAD''').<br><br>
=={{header|Scala}}==
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The different phases of the GC can be explicitly invoced to ''reclaim'' unused memory immediately, but it does not guarantee the reclaimed memory is deemed excessive and therefore will be returned to the OS.
▲=={{header|Racket}}==
▲Racket has a JIT compiler that translates functions to machine code whenever they are applied. When such a function is garbage-collected, the JITted machine code is released or re-used with it. Therefore, to reclaim some executable code segment, simply drop references to the function.
▲=={{header|REXX}}==
▲When using REXX in the (VM) CMS environment, the use of '''NUCXDROP''' can be used to release memory (virtual storage) that a REXX program is using (when previously loaded into virtual memory via '''NUCXLOAD''').<br><br>
=={{header|Tcl}}==
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