Don't format diameter_make:codec/2 errors

Instead, add diameter_make:format_error/1 to allow the caller to format
if desired, which is what applications like compiler and yecc do. Use
this to check that the expected error is the one actually generated in
the compiler suite.

1 files changed, 17 insertions, 1 deletions

diff --git a/lib/diameter/doc/src/diameter_make.xml b/lib/diameter/doc/src/diameter_make.xml
index 1c1eff6c6a..16ef49d4b2 100644
--- a/lib/diameter/doc/src/diameter_make.xml
+++ b/lib/diameter/doc/src/diameter_make.xml
@@ -16,7 +16,7 @@
 <header>
 <copyright>
 <year>2012</year>
-<year>2013</year>
+<year>2014</year>
 <holder>Ericsson AB. All Rights Reserved.</holder>
 </copyright>
 <legalnotice>
@@ -175,6 +175,10 @@ Note that a dictionary's <c>&dict_name;</c>, together with the
 The <c>&dict_name;</c> of a literal input dictionary defaults to
 <c>dictionary</c>.</p>
 
+<p>
+A returned error reason can be converted into a readable string using
+&format_error;.</p>
+
 </desc>
 </func>
 
@@ -206,6 +210,18 @@ The return value is also a parsed dictionary.</p>
 </desc>
 </func>
 
+<!-- ===================================================================== -->
+
+<func>
+<name>format_error(Reason) -> string()</name>
+<fsummary>Turn an error reason into a readable string.</fsummary>
+<desc>
+
+<p>
+Turn an error reason returned by &codec; into a readable string.</p>
+</desc>
+</func>
+
 </funcs>
 
 <!-- ===================================================================== -->