Parsing a comma-separated list of numbers and range specifications in Python

gistfile1.py

from itertools import chain

def parse_range(rng):
    parts = rng.split('-')
    if 1 > len(parts) > 2:
        raise ValueError("Bad range: '%s'" % (rng,))
    parts = [int(i) for i in parts]
    start = parts[0]
    end = start if len(parts) == 1 else parts[1]
    if start > end:
        end, start = start, end
    return range(start, end + 1)

def parse_range_list(rngs):
    return sorted(set(chain(*[parse_range(rng) for rng in rngs.split(',')])))

@sjaek

I made a version that supports negative numbers and sorts and collapses the ranges and only then expands them so it's easy on memory for large ranges.

danke!

In [8]: def status_code(v):
   ...:     if '*' == v:
   ...:         return list(range(200, 300))
   ...:     rv = []
   ...:     sp = v.split(',')
   ...:     for x in sp:
   ...:         if '-' in x:
   ...:             start, stop = map(int, x.split('-'))
   ...:             rv += range(start, stop + 1)
   ...:         else:
   ...:             rv += [int(x)]
   ...:     return rv
...
In [12]: status_code('200-204,206,301,302,400-404,500')
Out[12]: [200, 201, 202, 203, 204, 206, 301, 302, 400, 401, 402, 403, 404, 500]