import re


def find_gaps(seq):
    """
    Accepts a string and returns the positions of all of the gaps in the sequence
    :param seq: str
    :return: list of [start,end] of all of the gaps
    """
    match = re.finditer(r"-+", seq)
    positions = []
    for m in match:
        positions.append([m.start(),m.end()])
    return positions