from buffer import Buffer

# console is another singleton
console = None
class ConsoleBuffer(Buffer):
    btype    = 'console'
    modename = 'ipython'
    def __new__(cls, *args, **kwargs):
        global console
        if console is None:
            b = object.__new__(ConsoleBuffer, *args, **kwargs)
            console = b
        return console
    def __init__(self):
        Buffer.__init__(self)
        self.clear()
    def clear(self):
        lines = ['# Python Console\n',
                 "# Evaluate python expressions in the editor's context (self)\n",
                 '# Press Control-] to exit\n']
        console.set_data(''.join(lines), force=True)
    def name(self):
        return '*Console*'
    def changed(self):
        return False
    def close(self):
        global console
        console = None
    def readonly(self):
        return True