id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
12070	"Variable(""a._hidden"") does not raise TemplateSyntaxError"	Johannes Dollinger	alexdutton	"{{{
#!python
>>> Variable(""a._hidden"")
<Variable: 'a._hidden'>
>>> FilterExpression(""a._hidden"", p)
...
TemplateSyntaxError: Variables and attributes may not begin with underscores: 'a._hidden'
}}}

This should be consistent. 
"		closed	Template system	1.1		fixed	variable, filterexpression, private, underscore		Ready for checkin	1	0	0	0	0	0