Created a ParsedTemplate class.

pystache/parser.py

@@ -9,6 +9,8 @@ This module is only meant for internal use by the renderengine module.
 
 import re
 
+from template import ParsedTemplate
+
 
 DEFAULT_DELIMITERS = ('{{', '}}')
 END_OF_LINE_CHARACTERS = ['\r', '\n']
@@ -73,7 +75,7 @@ class Parser(object):
 
     def parse(self, template, index=0, section_key=None):
         """
-        Parse a template string into a parse tree.
+        Parse a template string into a ParsedTemplate instance.
 
         This method uses the current tag delimiter.
 
@@ -126,19 +128,19 @@ class Parser(object):
                 if tag_key != section_key:
                     raise ParsingError("Section end tag mismatch: %s != %s" % (repr(tag_key), repr(section_key)))
 
-                return parse_tree, template[start_index:match_index], end_index
+                return ParsedTemplate(parse_tree), template[start_index:match_index], end_index
 
             index = self._handle_tag_type(template, parse_tree, tag_type, tag_key, leading_whitespace, start_index, match_index, end_index)
 
         # Save the rest of the template.
         parse_tree.append(template[index:])
 
-        return parse_tree
+        return ParsedTemplate(parse_tree)
 
     def _parse_section(self, template, index_start, section_key):
-        parse_tree, template, index_end = self.parse(template=template, index=index_start, section_key=section_key)
+        parsed_template, template, index_end = self.parse(template=template, index=index_start, section_key=section_key)
 
-        return parse_tree, template, index_end
+        return parsed_template, template, index_end
 
     def _handle_tag_type(self, template, parse_tree, tag_type, tag_key, leading_whitespace, start_index, match_index, end_index):
 
@@ -162,13 +164,13 @@ class Parser(object):
 
         elif tag_type == '#':
 
-            buff, template, end_index = self._parse_section(template, end_index, tag_key)
-            func = engine._make_get_section(tag_key, buff, template, self._delimiters)
+            parsed_section, template, end_index = self._parse_section(template, end_index, tag_key)
+            func = engine._make_get_section(tag_key, parsed_section, template, self._delimiters)
 
         elif tag_type == '^':
 
-            buff, template, end_index = self._parse_section(template, end_index, tag_key)
-            func = engine._make_get_inverse(tag_key, buff)
+            parsed_section, template, end_index = self._parse_section(template, end_index, tag_key)
+            func = engine._make_get_inverse(tag_key, parsed_section)
 
         elif tag_type == '>':
 

pystache/renderengine.py

@@ -13,39 +13,6 @@ from parser import Parser
 NON_BLANK_RE = re.compile(r'^(.)', re.M)
 
 
-def render_parse_tree(parse_tree, context):
-    """
-    Returns: a string of type unicode.
-
-    The elements of parse_tree can be any of the following:
-
-     * a unicode string
-     * the return value of a call to any of the following:
-
-        * RenderEngine._make_get_literal():
-            Args: context
-            Returns: unicode
-        * RenderEngine._make_get_escaped():
-            Args: context
-            Returns: unicode
-        * RenderEngine._make_get_partial()
-            Args: context
-            Returns: unicode
-        * RenderEngine._make_get_section()
-            Args: context
-            Returns: unicode
-        * _make_get_inverse()
-            Args: context
-            Returns: unicode
-
-    """
-    get_unicode = lambda val: val(context) if callable(val) else val
-    parts = map(get_unicode, parse_tree)
-    s = ''.join(parts)
-
-    return unicode(s)
-
-
 class RenderEngine(object):
 
     """
@@ -175,7 +142,7 @@ class RenderEngine(object):
 
         return get_partial
 
-    def _make_get_inverse(self, name, parsed):
+    def _make_get_inverse(self, name, parsed_template):
         def get_inverse(context):
             """
             Returns a string with type unicode.
@@ -184,25 +151,28 @@ class RenderEngine(object):
             data = context.get(name)
             if data:
                 return u''
-            return render_parse_tree(parsed, context)
+            return parsed_template.render(context)
 
         return get_inverse
 
-    def _make_get_section(self, name, parse_tree_, template_, delims):
+    # TODO: the template_ and parsed_template_ arguments don't both seem
+    # to be necessary.  Can we remove one of them?  For example, if
+    # callable(data) is True, then the initial parsed_template isn't used.
+    def _make_get_section(self, name, parsed_template_, template_, delims):
         def get_section(context):
             """
             Returns: a string of type unicode.
 
             """
             template = template_
-            parse_tree = parse_tree_
+            parsed_template = parsed_template_
             data = context.get(name)
             if not data:
                 data = []
             elif callable(data):
                 # TODO: should we check the arity?
                 template = data(template)
-                parse_tree = self._parse_to_tree(template_string=template, delimiters=delims)
+                parsed_template = self._parse(template_string=template, delimiters=delims)
                 data = [ data ]
             elif type(data) not in [list, tuple]:
                 data = [ data ]
@@ -210,16 +180,16 @@ class RenderEngine(object):
             parts = []
             for element in data:
                 context.push(element)
-                parts.append(render_parse_tree(parse_tree, context))
+                parts.append(parsed_template.render(context))
                 context.pop()
 
             return unicode(''.join(parts))
 
         return get_section
 
-    def _parse_to_tree(self, template_string, delimiters=None):
+    def _parse(self, template_string, delimiters=None):
         """
-        Parse the given template into a parse tree using a new parser.
+        Parse the given template, and return a ParsedTemplate instance.
 
         """
         parser = Parser(self, delimiters=delimiters)
@@ -240,9 +210,9 @@ class RenderEngine(object):
         if type(template) is not unicode:
             raise Exception("Argument 'template' not unicode: %s: %s" % (type(template), repr(template)))
 
-        parse_tree = self._parse_to_tree(template_string=template)
+        parsed_template = self._parse(template_string=template)
 
-        return render_parse_tree(parse_tree, context)
+        return parsed_template.render(context)
 
     def render(self, template, context):
         """

pystache/template.py

+# coding: utf-8
+
+"""
+Exposes a class that represents a parsed (or compiled) template.
+
+This module is meant only for internal use.
+
+"""
+
+
+class ParsedTemplate(object):
+
+    def __init__(self, parse_tree):
+        self._parse_tree = parse_tree
+
+    def render(self, context):
+        """
+        Returns: a string of type unicode.
+
+        The elements of parse_tree can be any of the following:
+
+         * a unicode string
+         * the return value of a call to any of the following:
+
+            * RenderEngine._make_get_literal():
+                Args: context
+                Returns: unicode
+            * RenderEngine._make_get_escaped():
+                Args: context
+                Returns: unicode
+            * RenderEngine._make_get_partial()
+                Args: context
+                Returns: unicode
+            * RenderEngine._make_get_section()
+                Args: context
+                Returns: unicode
+            * _make_get_inverse()
+                Args: context
+                Returns: unicode
+
+        """
+        get_unicode = lambda val: val(context) if callable(val) else val
+        parts = map(get_unicode, self._parse_tree)
+        s = ''.join(parts)
+
+        return unicode(s)
+