def _build_reserved_words():
class _SamuraiEmptyCommand(Command): pass
Empty = _SamuraiEmptyCommand
return frozenset(filter(lambda x: not is_python_reserved_attr(x),
itertools.chain(Empty.__dict__.keys(),
Empty().__dict__.keys(),
Command.__dict__.keys()))) \
| frozenset(keyword.kwlist) \
| frozenset(("in", "out",))
def __new__(metacls, name, bases, namespace, **kwds):
# Do not do anything for base class Command.
if name == "Pool" and bases == (object,):
return super().__new__(metacls, name, bases, namespace, **kwds)
if Pool not in bases:
raise TypeError("cannot subclass custom pool")
### Prepare namespace
namespace.setdefault("depth", 1)
for attrname in namespace.keys():
if is_python_reserved_attr(attrname):
continue
if attrname != "depth":
raise TypeError("unknown attribute '{}' for Pool {}"
.format(attrname, name))
depth = namespace["depth"]
if not isinstance(depth, int):
raise TypeError("depth must be an int")
if depth < 1:
raise ValueError("depth must be greater or equal to 1")
### Finally create the class.
return super().__new__(metacls, name, bases, namespace, **kwds)
