types.py 文件源码

def __init__(self, name, *, default=None, description=None):
        self._name = str(name)
        self._description = str(description) or 'No description available'
        self._on_change = Signal()
        self._default = self._value = self._prev_value = None
        if default is not None:
            initial_value = self.convert(default)
            self.validate(initial_value)
            self._value = initial_value
            self._default = self._value
        log.debug('Initialized ValueBase: %s=%r', self._name, self._value)