Repository : ssh://darcs.haskell.org//srv/darcs/ghc On branch : master
http://hackage.haskell.org/trac/ghc/changeset/57b1d54a56b406648dd198092419441b990b3ae1 >--------------------------------------------------------------- commit 57b1d54a56b406648dd198092419441b990b3ae1 Author: Ian Lynagh <[email protected]> Date: Sat Jan 14 13:40:58 2012 +0000 Document the Num superclass divergence from H98/H2010 >--------------------------------------------------------------- docs/users_guide/bugs.xml | 33 +++++++++++++++++++++++++++++++++ 1 files changed, 33 insertions(+), 0 deletions(-) diff --git a/docs/users_guide/bugs.xml b/docs/users_guide/bugs.xml index 12ef946..9da7927 100644 --- a/docs/users_guide/bugs.xml +++ b/docs/users_guide/bugs.xml @@ -150,6 +150,39 @@ main = do args <- getArgs <variablelist> <varlistentry> + <term>Num superclasses</term> + <listitem> + <para> + The <literal>Num</literal> class does not have + <literal>Show</literal> or <literal>Eq</literal> + superclasses. + </para> + + <para> + You can make code that works with both + Haskell98/Haskell2010 and GHC by: + <itemizedlist> + <listitem> + <para> + Whenever you make a <literal>Num</literal> instance + of a type, also make <literal>Show</literal> and + <literal>Eq</literal> instances, and + </para> + </listitem> + <listitem> + <para> + Whenever you give a function, instance or class a + <literal>Num t</literal> constraint, also give it + <literal>Show t</literal> and + <literal>Eq t</literal> constraints. + </para> + </listitem> + </itemizedlist> + </para> + </listitem> + </varlistentry> + + <varlistentry> <term>Multiply-defined array elements—not checked:</term> <listitem> <para>This code fragment should _______________________________________________ Cvs-ghc mailing list [email protected] http://www.haskell.org/mailman/listinfo/cvs-ghc
