# $Id$
# element cloning demo
import cElementTree as ET
# import elementtree.ElementTree as ET
##
# Turns an element tree into a cloning factory. The callable object
# returned by this function returns copies of the original tree.
#
# @param elem An element tree.
# @return A callable factory object.
def make_factory(elem):
def generate_elem(append, elem, level):
var = "e" + str(level)
arg = repr(elem.tag)
if elem.attrib:
arg += ", **%r" % elem.attrib
if level == 1:
append(" e1 = Element(%s)" % arg)
else:
append(" %s = SubElement(e%d, %s)" % (var, level-1, arg))
if elem.text:
append(" %s.text = %r" % (var, elem.text))
if elem.tail:
append(" %s.tail = %r" % (var, elem.tail))
for e in elem:
generate_elem(append, e, level+1)
# generate code for a function that creates a tree
output = ["def element_factory():"]
generate_elem(output.append, elem, 1)
output.append(" return e1")
# setup global function namespace
namespace = {"Element": ET.Element, "SubElement": ET.SubElement}
# create function object
exec "\n".join(output) in namespace
return namespace["element_factory"]
# --------------------------------------------------------------------
# demo code
import copy
DOC1 = "text
"
DOC2 = """\
text
texttail
"""
tree = ET.XML(DOC1)
clone_factory = make_factory(tree)
def test0():
make_factory(tree)
def test1():
return copy.deepcopy(tree)
def test2():
return clone_factory()
# make sure they produce the same output
print ET.tostring(test1())
print ET.tostring(test2())
# to benchmark, use
# timeit -s "import clone" "clone.test1()"
# timeit -s "import clone" "clone.test2()"