def finditer_alt(pattern, iterable):
"""
An experimental implementation of finditer.
The idea here is to make an implementation that is able to work with any
iterator, not necessariry the indexable ones.
This implies (among other things) that each element is feeded only once and
then discarded.
"""
assert isinstance(pattern, Pattern)
pattern = Star(Star(Any(), greedy=False) + Group(pattern, None))
code = pattern.compile()
vm = VirtualMachine(code)
m = Match()
new = Match()
# Start VM
vm.do_epsilon_transitions()
vm.cutoff()
for x in iterable:
if not vm.is_alive():
break
vm.feed(x)
vm.do_epsilon_transitions()
new.state = vm.accepting_state(None)
if new.state != None:
if m.state == None:
m.state = new.state
elif m.start() == new.start() and m.end() < new.end():
m.state = new.state
elif m.start() != new.start():
yield m
m = new
new = Match()
vm.cutoff()
if m.state != None:
yield m
def _match(pattern, iterable):
assert isinstance(pattern, Pattern)
code = pattern.compile()
vm = VirtualMachine(code)
m = Match()
# Start VM
vm.do_epsilon_transitions()
m.state = vm.accepting_state(None)
vm.cutoff()
for x in iterable:
if not vm.is_alive():
break
vm.feed(x)
vm.do_epsilon_transitions()
m.state = vm.accepting_state(m.state)
vm.cutoff()
if m.state == None:
return None
return m