<item> imported HBC's quick-sort algorithm from @QSort@ into @List@.
+<item> added support for assertions. Conceptually, a new function has
+ been added to the Prelude with the following type:
+
+ <tscreen> <verb>
+ assert :: Bool -> a -> a
+ </verb> </tscreen>
+
+ which has the following behaviour:
+
+ <tscreen> <verb>
+ assert pred v
+ | pred = v
+ | otherwise = error "assertion failed"
+ </verb> </tscreen>
+
+ However in this form, the practical use of assertions is
+ limited as no indication is given as to what assertion failed.
+ So to help out here, ghc will rewrite any uses of <tt/assert/
+ to instead invoke the function <tt/assert__/ :
+
+ <tscreen> <verb>
+ assert__ :: String -> Bool -> a -> a
+ </verb> </tscreen>
+
+ where the first argument to <tt/assert__/ is a compiler generated string
+ which encodes the source location of the original <tt/assert/.
+
+ Assertions are a Glasgow extension, so -fglasgow-exts is
+ needed to use them.
+
</itemize>