Extend URL variable expansion syntax and add source links to the contents page

Like the wiki link on the contents and index page, add a source code link too.
Extend the wiki & source URL variable expansion syntax.

The original syntax was:
%F for the source file name (the .hs version only, not the .lhs or .hs.pp one)
%M for the module name (with '.' replaced by '/')

The new syntax is:
%F or %{FILE} for the original source file name
%M or %{MODULE} for the module name (no replacements)
%N or %{NAME} for the function/type export name
%K or %{KIND} for a type/value flag "t" or "v"

with these extensions:
%{MODULE/./c} to replace the '.' module seperator with any other char c

%{VAR|some text with the % char in it} which means if the VAR is not in use in
this URL context then "" else replace the given text with the '%' char
replaced by the string value of the VAR. This extension allows us to construct
URLs wit optional parts, since the module/file name is not available for the
URL in the contents/index pages and the value/type name is not available for
the URL at the top level of each module.

1 files changed, 4 insertions, 2 deletions

diff --git a/src/Main.hs b/src/Main.hs
index 1f76fe47..491eeccf 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -236,12 +236,14 @@ run flags files = do
 
   when (Flag_GenContents `elem` flags) $ do
 	ppHtmlContents odir title package maybe_html_help_format
-            maybe_index_url maybe_wiki_url visible_read_ifaces prologue
+            maybe_index_url maybe_source_url maybe_wiki_url
+            visible_read_ifaces prologue
         copyHtmlBits odir libdir css_file
 
   when (Flag_GenIndex `elem` flags) $ do
 	ppHtmlIndex odir title package maybe_html_help_format
-            maybe_contents_url maybe_wiki_url visible_read_ifaces
+            maybe_contents_url maybe_source_url maybe_wiki_url
+            visible_read_ifaces
         copyHtmlBits odir libdir css_file
         
   when (Flag_GenContents `elem` flags && Flag_GenIndex `elem` flags) $ do