Regexp for matching executable version number

Question

I'm trying to write a regular expression for matching executable version number.
It can be provided in two ways:

• MAJOR.MINOR.TINY
• MAJOR.MINOR.TINY.BUILD_NUMBER

I do not need to parse these values, just check for match. So, I can: ^\\d+[\\.\\d+]*$ . Ok, but this regexp will match strings with 5 and more version parts, ie 1.2.3.4.5 . Also, it will match string like 1..2.3 . It would be great to do something like ^[as many digits as you want and only one .]{3,4}$ .

PS Of course, I can check for something like this ^(\\d*)\\.(\\d*)\\.(\\d*)$ at first and the for ^(\\d*)\\.(\\d*)\\.(\\d*)\\.(\\d*)$ if not matched. But maybe there is a better (smarter) way to do this.

I use re python module for checking the match:

import re

version_regexp = re.compile(r'^\d+[\.\d+]*$')
versions = ['dsvfsdf',
            '1.a.3',
            '1.2.4',
            '1.4..5.6',
            '0.3.1',
            'a.b.c.d',
            '1,2,3']
for i, sample in enumerate(versions):
    print('Sample[%d]: %s' % (i, True if version_regexp.match(sample) else False))

Thank you in advance!

Answer 1

正则表达式应类似于re.compile(r'^\\d+(\\.\\d+){2,3}$')