support for posix regexp in dal (sqlite and postgresql)

VERSION

@@ -1 +1 @@
-Version 1.99.4 (2012-02-26 15:42:22) stable
+Version 1.99.4 (2012-02-26 16:03:31) stable

gluon/dal.py

@@ -962,6 +962,10 @@ class BaseAdapter(ConnectionPool):
         items = ','.join(self.expand(item, first.type) for item in second)
         return '(%s IN (%s))' % (self.expand(first), items)
 
+    def REGEXP(self, first, second):
+        "regular expression operator"
+        raise NotImplementedError
+
     def LIKE(self, first, second):
         "case sensitive like operator"
         raise NotImplementedError
@@ -1721,6 +1725,10 @@ class SQLiteAdapter(BaseAdapter):
     def lastrowid(self, table):
         return self.cursor.lastrowid
 
+    def REGEXP(self,first,second):
+        return '(%s REGEXP %s)' % (self.expand(first),
+                                   self.expand(second,'string'))
+
     def _select(self, query, fields, attributes):
         """
         Simulate SELECT ... FOR UPDATE with BEGIN IMMEDIATE TRANSACTION.
@@ -1998,6 +2006,10 @@ class PostgreSQLAdapter(BaseAdapter):
         return '(%s ILIKE %s)' % (self.expand(first),
                                   self.expand(second,'string'))
 
+    def REGEXP(self,first,second):
+        return '(%s ~ %s)' % (self.expand(first),
+                              self.expand(second,'string'))
+
     def STARTSWITH(self,first,second):
         return '(%s ILIKE %s)' % (self.expand(first),
                                   self.expand(second+'%','string'))
@@ -6913,6 +6925,9 @@ class Expression(object):
         op = case_sensitive and self.db._adapter.LIKE or self.db._adapter.ILIKE
         return Query(self.db, op, self, value)
 
+    def regex(self, value):
+        return Query(self.db, self.db._adapter.REGEXP, self, value)
+
     def belongs(self, value):
         if isinstance(value,Query):
             value = self.db(value)._select(value.first._table._id)