1 files changed, 77 insertions, 0 deletions
diff --git a/grc/core/blocks/_templates.py b/grc/core/blocks/_templates.py
new file mode 100644
index 0000000000..0b15166423
--- /dev/null
+++ b/grc/core/blocks/_templates.py
@@ -0,0 +1,77 @@
+# Copyright 2016 Free Software Foundation, Inc.
+# This file is part of GNU Radio
+#
+# GNU Radio Companion 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.
+#
+# GNU Radio Companion 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
+"""
+This dict class holds a (shared) cache of compiled mako templates.
+These
+
+"""
+from __future__ import absolute_import, print_function
+
+from mako.template import Template
+from mako.exceptions import SyntaxException
+
+from ..errors import TemplateError
+
+
+class MakoTemplates(dict):
+
+    _template_cache = {}
+
+    def __init__(self, _bind_to=None, *args, **kwargs):
+        self.instance = _bind_to
+        dict.__init__(self, *args, **kwargs)
+
+    def __get__(self, instance, owner):
+        if instance is None or self.instance is not None:
+            return self
+        copy = self.__class__(_bind_to=instance, **self)
+        if getattr(instance.__class__, 'templates', None) is self:
+            setattr(instance, 'templates', copy)
+        return copy
+
+    @classmethod
+    def compile(cls, text):
+        text = str(text)
+        try:
+            template = Template(text)
+        except SyntaxException as error:
+            raise TemplateError(text, *error.args)
+
+        cls._template_cache[text] = template
+        return template
+
+    def _get_template(self, text):
+        try:
+            return self._template_cache[str(text)]
+        except KeyError:
+            return self.compile(text)
+
+    def render(self, item):
+        text = self.get(item)
+        if not text:
+            return ''
+        namespace = self.instance.namespace_templates
+
+        try:
+            if isinstance(text, list):
+                templates = (self._get_template(t) for t in text)
+                return [template.render(**namespace) for template in templates]
+            else:
+                template = self._get_template(text)
+                return template.render(**namespace)
+        except Exception as error:
+            raise TemplateError(error, text)