The provider: TALES expression is supported since Five 1.4. Five 1.5 is included

in Zope 2.10 now, so we could just as well register it here. Gets rid of some
stupid code duplication in Five as well...

lib/python/Products/PageTemplates/Expressions.py

@@ -22,6 +22,7 @@ from zope.tales.expressions import PathExpr, StringExpr, NotExpr
 from zope.tales.expressions import DeferExpr, SubPathExpr
 from zope.tales.expressions import SimpleModuleImporter
 from zope.traversing.adapters import traversePathElement
+from zope.contentprovider.tales import TALESProviderExpression
 
 from zExceptions import NotFound, Unauthorized
 from OFS.interfaces import ITraversable
@@ -107,6 +108,7 @@ def Engine():
     e.registerType('not', NotExpr)
     e.registerType('defer', DeferExpr)
     e.registerType('lazy', LazyExpr)
+    e.registerType('provider', TALESProviderExpression)
     e.registerBaseName('modules', SecureModuleImporter)
     return e