pre-release updates, bug fixes
diff --git a/pretty_yaml.py b/pretty_yaml.py
new file mode 100644
index 0000000..44d4e49
--- /dev/null
+++ b/pretty_yaml.py
@@ -0,0 +1,75 @@
+def dumps_simple(val):
+ bad_symbols = set(" \r\t\n,':")
+
+ if isinstance(val, basestring):
+ if len(bad_symbols & set(val)) != 0:
+ return repr(val)
+ return val
+ elif val is True:
+ return 'true'
+ elif val is False:
+ return 'false'
+ elif val is None:
+ return 'null'
+
+ return str(val)
+
+
+def is_simple(val):
+ simple_type = isinstance(val, (str, unicode, int, long, bool, float))
+ return simple_type or val is None
+
+
+def all_nums(vals):
+ return all(isinstance(val, (int, float, long)) for val in vals)
+
+
+def dumpv(data, tab_sz=4, width=120, min_width=40):
+ tab = ' ' * tab_sz
+
+ if width < min_width:
+ width = min_width
+
+ res = []
+ if is_simple(data):
+ return [dumps_simple(data)]
+
+ if isinstance(data, (list, tuple)):
+ if all(map(is_simple, data)):
+ if all_nums(data):
+ one_line = "[{}]".format(", ".join(map(dumps_simple, data)))
+ else:
+ one_line = "[{}]".format(",".join(map(dumps_simple, data)))
+ else:
+ one_line = None
+
+ if one_line is None or len(one_line) > width:
+ pref = "-" + ' ' * (tab_sz - 1)
+
+ for val in data:
+ items = dumpv(val, tab_sz, width - tab_sz, min_width)
+ items = [pref + items[0]] + \
+ [tab + item for item in items[1:]]
+ res.extend(items)
+ else:
+ res.append(one_line)
+ elif isinstance(data, dict):
+ assert all(map(is_simple, data.keys()))
+
+ for k, v in data.items():
+ key_str = dumps_simple(k) + ": "
+ val_res = dumpv(v, tab_sz, width - tab_sz, min_width)
+
+ if len(val_res) == 1 and len(key_str + val_res[0]) < width:
+ res.append(key_str + val_res[0])
+ else:
+ res.append(key_str)
+ res.extend(tab + i for i in val_res)
+ else:
+ raise ValueError("Can't pack {0!r}".format(data))
+
+ return res
+
+
+def dumps(data, tab_sz=4, width=120, min_width=40):
+ return "\n".join(dumpv(data, tab_sz, width, min_width))