return date string using regex

Question

I am trying to return the date from a longer string. The date could be any weekday, any number with a subscript st, nd, rd, th and the month as 3 string values (Jan, Feb etc).

This is my attempt but I'm getting None. Not sure what I'm missing?

string = 'Times for Saturday 10th Aug'

days = ('Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday')
months = ('Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec')
pat = re.compile(r'^(%s) (\d+)(st|nd|rd|th) (%s)$' %
                 ('|'.join(days), '|'.join(months)))

print(re.match(pat, string))

`^` means the start of line. What happens when you remove that? — Selcuk, Oct 11 '19 at 00:49

score 1 · Accepted Answer · answered Oct 11 '19 at 00:50

1

A caret ^ in a regex and re.match both start matching at the start of the string. Simply remove the caret and use re.search instead.

pat = re.compile(r'(%s) (\d+)(st|nd|rd|th) (%s)$' %
                 ('|'.join(days), '|'.join(months)))

print(re.search(pat, string))

answered Oct 11 '19 at 00:50

wjandrea

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Thanks @wjandrea. I want to pass the date string to another call function. It's returning ``. I'm only after `Saturday 10th Aug` – jonboy Oct 11 '19 at 00:57
@jonboy See [How do I return a string from a regex match in python?](https://stackoverflow.com/q/18493677/4518341) – wjandrea Oct 11 '19 at 01:01
Cheers. Thanks @wjandrea – jonboy Oct 11 '19 at 02:05

score 1 · Answer 2 · answered Oct 11 '19 at 01:49

You should remove the beginning of line character ^ and the end of the line character $, then everything works just fine:

>>> re.findall(r'(%s) (\d+)(st|nd|rd|th) (%s)' %
...                  ('|'.join(days), '|'.join(months)), string)
[('Saturday', '10', 'th', 'Aug')]

And, please, don't call variable string -- it's already used in python.

return date string using regex

2 Answers2