newitem: remove ExtractorField and port googledir example

--HG--
extra : convert_revision : svn%3Ab85faa78-f9eb-468e-a121-7cced6da292c%40905

scrapy/trunk/examples/contrib_exp/googledir/googledir/items.py

@@ -2,8 +2,8 @@
 
 from scrapy.contrib_exp import newitem 
 
-from scrapy.contrib_exp.newitem import extractors
-from scrapy.contrib_exp import adaptors
+from scrapy.contrib_exp.newitem.extractors import ItemExtractor, adaptor
+from scrapy.contrib_exp.adaptors import extract, strip
 
 
 class GoogledirItem(newitem.Item):
@@ -12,9 +12,9 @@ class GoogledirItem(newitem.Item):
     description = newitem.StringField()
 
 
-class GoogledirItemExtractor(extractors.ItemExtractor):
+class GoogledirItemExtractor(ItemExtractor):
     item_class = GoogledirItem
 
-    name = extractors.ExtractorField([adaptors.extract, adaptors.strip])
-    url = extractors.ExtractorField([adaptors.extract, adaptors.strip])
-    description = extractors.ExtractorField([adaptors.extract, adaptors.strip])
+    name = adaptor(extract, strip)
+    url = adaptor(extract, strip)
+    description = adaptor(extract, strip)

scrapy/trunk/scrapy/contrib_exp/newitem/extractors.py

@@ -38,38 +38,6 @@ class ItemExtractor(object):
             return object.__getattribute__(self, name)
 
 
-class ExtractorField(object):
-    def __init__(self, funcs):
-        if not hasattr(funcs, '__iter__'):
-            raise TypeError(
-                'You must initialize ExtractorField with a list of callables')
-
-        self._funcs = []
-
-        for func in funcs:
-            func_args = get_func_args(func)
-            takes_args = True if 'adaptor_args' in func_args else False
-            self._funcs.append((func, takes_args))
-
-    def __call__(self, value, adaptor_args=None):
-        values = [value]
-
-        for func, takes_args in self._funcs:
-            next_round = []
-
-            for val in values:
-                val = func(val, adaptor_args) if takes_args else func(val)
-
-                if isinstance(val, tuple):
-                    next_round.extend(val)
-                elif val is not None:
-                    next_round.append(val)
-
-            values = next_round
-
-        return list(values)
-
-
 def adaptor(*funcs, **adaptor_args):
     """A pipe adaptor implementing the tree adaption logic