* This release includes a security fix for a DoS vulnerability of REXML.
* Some bug fixes are also included
# New Features
* Language core features
- Keyword arguments, which give flexibility to API design
- Module#prepend, which is a new way to extend a class
- A literal %i, which creates an array of symbols easily
- __dir__, which returns the dirname of the file currently being executed
- The UTF-8 default encoding, which make many magic comments omissible
* Built-in libraries
- Enumerable#lazy and Enumerator::Lazy, for (possibly infinite) lazy stream
- Enumerator#size and Range#size, for lazy size evaluation
- #to_h, which is a new convention for conversion to Hash
- Onigmo, which is a new regexp engine (a fork of Oniguruma)
- Asynchronous exception handling API
* Debug support
- DTrace support, which enables run-time diagnosis in production
- TracePoint, which is an improved tracing API
* Performance improvements
- GC optimization by bitmap marking
- Kernel#require optimization which makes Rails startup very fast
- VM optimization such as method dispatch
- Float operation optimization
Download Accelerator Plus 10.0.4.3
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* Many new methods
* New socket API (enhanced IPv6 support)
* New encodings
* Random class that supports various random number generators
* Time is reimplemented. There is no longer the year 2038 problem.
* some regexp enhancements
* $: no longer includes the current directory.
* dl is reimplemented on top of libffi.
* new psych library that wraps libyaml. You can use the library instead of syck.