branch for universe

[helm.git] / components / syntax_extensions / pa_unicode_macro.ml

diff --git a/components/syntax_extensions/pa_unicode_macro.ml b/components/syntax_extensions/pa_unicode_macro.ml
new file mode 100644 (file)
index 0000000..d81ec21
--- /dev/null
+++ b/components/syntax_extensions/pa_unicode_macro.ml
@@ -0,0 +1,61 @@
+(* Copyright (C) 2004, HELM Team.
+ * 
+ * This file is part of HELM, an Hypertextual, Electronic
+ * Library of Mathematics, developed at the Computer Science
+ * Department, University of Bologna, Italy.
+ * 
+ * HELM is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ * 
+ * HELM is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with HELM; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA  02111-1307, USA.
+ * 
+ * For details, see the HELM World-Wide-Web page,
+ * http://helm.cs.unibo.it/
+ *)
+
+(* $Id$ *)
+
+let debug = false
+let debug_print s = if debug then prerr_endline (Lazy.force s)
+
+let loc = Stdpp.make_loc (-1, -1)
+
+let expand_unicode_macro macro =
+  debug_print (lazy (Printf.sprintf "Expanding macro '%s' ..." macro));
+  let expansion = Utf8Macro.expand macro in
+  <:expr< $str:expansion$ >>
+
+let _ =
+  Quotation.add "unicode"
+    (Quotation.ExAst (expand_unicode_macro, (fun _ -> assert false)))
+
+open Pa_extend
+
+EXTEND
+  symbol: FIRST
+    [
+      [ x = UIDENT; q = QUOTATION ->
+        let (quotation, arg) =
+          let pos = String.index q ':' in
+          (String.sub q 0 pos,
+           String.sub q (pos + 1) (String.length q - pos - 1))
+        in
+        debug_print (lazy (Printf.sprintf "QUOTATION = %s; ARG = %s" quotation arg));
+        if quotation = "unicode" then 
+          AStok (loc, x, Some (ATexpr (loc, expand_unicode_macro arg)))
+        else
+          assert false
+      ]
+    ];
+END
+