7.15. Regex Quantifier Lazy
Quantifier specifies how many occurrences of preceding qualifier or character class
Prefer shortest matches
Works better with strings
Not that good results for numbers
Non-greedy
{n,m}?- minimum n repetitions, maximum m times, prefer shorter{,n}?- maximum n repetitions, prefer shorter{n,}?- minimum n repetitions, prefer shorter{0,1}?- minimum 0 repetitions, maximum 1 repetitions (maybe)
7.15.1. SetUp
>>> import re
7.15.2. Bounded
>>> string = 'On Sun, Jan 1st, 2000 at 12:00 AM Alice <alice@example.com> wrote'
>>> re.findall(r'\d{2,4}?', string)
['20', '00', '12', '00']
7.15.3. No Upper-Bound
>>> string = 'On Sun, Jan 1st, 2000 at 12:00 AM Alice <alice@example.com> wrote'
>>> re.findall(r'\d{2,}?', string)
['20', '00', '12', '00']
7.15.4. No Lower-Bound
>>> string = 'On Sun, Jan 1st, 2000 at 12:00 AM Alice <alice@example.com> wrote'
>>> re.findall(r'\d{,4}?', string)
['', '', '', '', '', '', '', '', '', '', '', '', '', '1', '', '',
'', '', '', '2', '', '0', '', '0', '', '0', '', '', '', '', '',
'1', '', '2', '', '', '0', '', '0', '', '', '', '', '', '', '',
'', '', '', '', '', '', '', '', '', '', '', '', '', '', '', '',
'', '', '', '', '', '', '', '', '', '', '', '', '']