[Minor tweaks to ch20.
Bryan O'Sullivan <bos@serpentine.com>**20080604065327] {
hunk ./en/book-shortcuts.xml 24
-<!ENTITY IO "<literal>IO</literal>">
+<!ENTITY IO "<type>IO</type>">
hunk ./en/ch17-monad-trans.xml 472
-  <sect1>
+  <sect1 id="monadtrans.maybet">
hunk ./en/ch20-errors.xml 7
-    Error handling is one of the most important -- and overlooked --
-    topics for programmers, regardless of the language used.  In
+    Error handling is one of the most important&emdash;and overlooked&emdash;topics for programmers, regardless of the language used.  In
hunk ./en/ch20-errors.xml 57
-      lazy evaluation at work -- it calculated results as needed.
+      lazy evaluation at work&emdash;it calculated results as needed.
hunk ./en/ch20-errors.xml 155
-          -- or even just filter out the problem results if desired.
+         &emdash;or even just filter out the problem results if desired.
hunk ./en/ch20-errors.xml 322
-  <!-- FIXME: ErrorT discussion -->
-
hunk ./en/ch20-errors.xml 338
-      Some problems -- especially those involving I/O -- call for
+      Some problems&emdash;especially those involving I/O&emdash;call for
hunk ./en/ch20-errors.xml 344
-      exceptions are -- surprise -- functions.
+      exceptions are&emdash;surprise&emdash;functions.
hunk ./en/ch20-errors.xml 511
-        a special module -- <literal>System.IO.Error</literal> exists
+        a special module&emdash;<literal>System.IO.Error</literal> exists
hunk ./en/ch20-errors.xml 526
+	<title>Be careful which names you use</title>
hunk ./en/ch20-errors.xml 534
-          module or the other.  Also, note that
-          <literal>Prelude</literal> defines the
-          <literal>System.IO.Error</literal> version of &catch;.
+          module or the other.</para>
+
+	<para>Note that <literal>Prelude</literal> exports
+          <literal>System.IO.Error</literal>'s version of &catch;,
+          <emphasis>not</emphasis> the version provided by
+          <code>Control.Exception</code>.  Remember that the former
+          can only catch I/O errors, while the latter can catch all
+          exceptions.  In other words, the &catch; in
+          <code>Control.Exception</code> is almost always the one you
+          will want, but it is <emphasis>not</emphasis> the one you
+          will get by default.
hunk ./en/ch20-errors.xml 605
-        &Exception; by hand -- or to have already have one on hand to
+        &Exception; by hand&emdash;or to have already have one on hand to
}