#!/usr/bin/env python

import yaml
import six

load = yaml.load # str, file

def load_fn(fn, dv=None):
	o = dv
	with open(fn, 'rb') as f:
		try:
			o = load(f)
		except:
			pass
	return o

dump = yaml.dump

def dump_no_flow(o):
	def represent_str(dumper, instance):
		tag = 'tag:yaml.org,2002:str'
		style = '|' if '\n' in instance else None
		return dumper.represent_scalar( tag, instance, style=style )

	for typ in [ str ] + ( [ unicode ] if six.PY2 else [] ):
		yaml.add_representer(typ, represent_str)

	return dump( o, default_flow_style=False, allow_unicode=True, encoding='utf-8' )

def save(o, fn, dv=''): # no_flow
	s = dump_no_flow(o)
	with open(fn, 'wb') as f:
		try:
			f.write(s)
		except:	
			return dv
	return s

# EOF