ROLL 1.0: $\omega$-Regular Language Learning Library
We present ROLL 1.0, an $\omega$-regular language learning library with command line tools to learn and complement B"uchi automata. This open source Java library implements all existing learning algorithms for the complete class of $\omega$-regular languages. In addition to that, new B"uchi automata operations such as complementation based on learning have been added into ROLL. The tool accepts a B"uchi automaton represented in the Hanoi Omega Automata Format and in the BA format used by the tool RABIT. Besides being useful to researchers, its Jupyter notebook can also be used in interactive environments to teach automata learning algorithms, especially the B"uchi automata learning.