ANNOUNCE: GHC version 7.4.1
igloo at earth.li
Thu Feb 2 21:51:13 CET 2012
The (Interactive) Glasgow Haskell Compiler -- version 7.4.1
The GHC Team is pleased to announce a new major release of GHC, 7.4.1.
Here are some of the highlights of the 7.4 branch since 7.2 and 7.0:
* The Num class no longer has Eq or Show superclasses.
* There is a new feature Safe Haskell (-XSafe, -XTrustworthy, -XUnsafe).
The design has changed since 7.2.
* There is a new feature kind polymorphism (-XPolyKinds).
A side-effect of this is that, when the extension is not enabled, in
certain circumstances kinds are now defaulted to * rather than being
* There is a new feature constraint kinds (-XConstraintKinds).
* It is now possible to give any sort of declaration at the ghci prompt.
For example, you can now declare datatypes within ghci.
* The profiling and hpc implementations have been merged and overhauled.
Visible changes include renaming of profiling flags, and a new
semantics for the cost-centre stacks (which should in most cases
result in more useful and intuitive profiles). The +RTS -xc flag now
also gives a stack trace.
* It is now possible to write compiler plugins.
* DPH support has been significantly improved.
* There is now preliminary support for registerised compilation using
LLVM on the ARM platform.
Full release notes are here:
How to get it
The easy way is to go to the web page, which should be self-explanatory:
We supply binary builds in the native package format for many
platforms, and the source distribution is available from the same
Packages will appear as they are built - if the package for your
system isn't available yet, please try again later.
Haskell is a standard lazy functional programming language.
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an optimising compiler generating good code for a variety of
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