Adobe releases a new AIR SDK version 3.4, it’s comes with Adobe ActionScript Compiler 2.0 (ASC 2.0).
ASC 2.0 is a new compiler for ActionScript® 3.0 (AS3). It has stricter adherence to the AS3 language specification, includes compilation performance improvements, is more stable under memory pressure, and contains some demonstration optimizations that can be optionally enabled (in-lining, dead code elimination). This is the same compiler that is included with Flash Builder® 4.7 Preview, packaged up as a stand-alone command-line compiler and made available in a distribution combined with AIR SDK 3.4.
Note: ASC 2.0 supports compiling AS3 applications. It still exposes familiar mxmlc and compc command-line entry points but it does not support compiling Flex application.
For mor info : Adobe Lab
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