Source code for priops.priop

class Priop(list):
    """A graph of edges."""

    def __init__(self, name=None, *args, **kwargs):
        """Sets up a new Priop named *name* (optional).  The constructor
        accepts all the various formats that ``list`` accepts."""

        list.__init__(self, *args, **kwargs)

        self.name = name

    def __str__(self):
        """Returns a pretty-formatted string (human readable), describing the
        Priop."""
        return '(' + self.name + ', defined by:\n    ' + \
            '\n*   '.join(map(str, self)) + '\n)'

    def __add__(self, other_priop):
        """Concatenates both the list items as well as the names.  If the 
        names are the same, the name is kept."""

        if self.name == other_priop.name:
            return Priop(list.__add__(self, other_priop), name=self.name)
        else:
            return Priop(list.__add__(self, other_priop),
                name=', '.join([self.name, other_priop.name]))