flasm - 1.62-10 main

Flasm disassembles your entire SWF including all the timelines and
events. Looking at disassembly, you learn how the Flash compiler works.
You can also do some optimization on the disassembled code by hand or
adjust the code as you wish. Flasm can then re-assemble the bytecode
into a new SWF.
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It is also possible to embed Flasm actions in your ActionScript, making
optimization of large projects more comfortable.
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Flasm is not a decompiler. What you get is the human readable
representation of SWF bytecode, not ActionScript source.
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Flasm can also compress and decompress SWF files.
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Flasm does not and may never work with Flash 9 files since Flash 9 is
a new virtual machine and support for it would mean a full rewrite.