<filename>.hcr</filename>. The Core format is described in <ulink url="../../core.pdf">
<citetitle>An External Representation for the GHC Core Language</citetitle></ulink>,
and sample tools
- for manipulating Core files (in Haskell) are in the GHC source distribution
- directory under <literal>utils/ext-core</literal>.
- Note that the format of <literal>.hcr</literal>
+ for manipulating Core files (in Haskell) are available in the
+ <ulink url="http://hackage.haskell.org/package/extcore">extcore package on Hackage</ulink>. Note that the format of <literal>.hcr</literal>
files is <emphasis>different</emphasis> from the Core output format that GHC generates
for debugging purposes (<xref linkend="options-debugging"/>), though the two formats appear somewhat similar.</para>