Custom base types

[hcoop/domtool2.git] / src / baseTypes.sml

diff --git a/src/baseTypes.sml b/src/baseTypes.sml
new file mode 100644 (file)
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+++ b/src/baseTypes.sml
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+(* HCoop Domtool (http://hcoop.sourceforge.net/)
+ * Copyright (c) 2006, Adam Chlipala
+ *
+ * This program 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.
+ *
+ * This program 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 this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*)
+
+(* Add some base types *)
+
+structure BaseTypes :> BASE_TYPES = struct
+
+open Ast
+
+val _ = Env.registerType ("even", fn (EInt n, _) => n mod 2 = 0
+                                  | _ => false)
+
+val _ = Env.registerType ("digits", fn (EString s, _) => CharVector.all Char.isDigit s
+                                  | _ => false)
+
+end