ranges_functionl.py

# -- Filter --
def filter_range(range_start, range_end, *exclusions):    
    def make_prange(start, stop):
        return lambda x: start <= x <= stop

    exclusion_predicates = [make_prange(start, stop)
                            for (start, stop) in exclusions]
        
    filtered_range = (n for n in range(range_start, range_end + 1)
                      if not any(ef(n) for ef in exclusion_predicates))
    return filtered_range
# [1, 2, ... 10, 21, 22, ... 30, 41, 42, ... 48, 50]

# -- Compress --
def zipped_range(rng):
    el0 = next(rng)
    for el in rng:
        yield (el0, el)
        el0 = el
# [(1, 2), ..., (9, 10), (10, 21), (21, 22), ... (48, 49), (49, 50)
        
def compressor(rng):
    zrng = zipped_range(filtered_range)
    el0, el1 = next(zrng)
    yield el0
    for (el0, el1) in zrng:
        if el0 != el1 - 1:
            yield el0
            yield el1
    yield el1
# [1, 10, 21, 30, 41, 50]
    
def extractor(rng):
    crng = compressor(rng)
    return zip(crng, crng)
# [(1, 10), (21, 30), (41, 50)]


# ---------------------------------------
full_range = (1, 50)
removable_ranges = [(11,20), (31,40)]

filtered_range = filter_range(1, 50, (11, 20), (31, 40))
#print(list(filtered_range))
print(list(extractor(filtered_range)))