正则表达式两组匹配一切直到模式

Question

I have the following examples:

Tortillas Bolsa 2a 1kg 4118
Tortillinas 50p 1 31Kg TAB TR 46113
Bollos BK 4in 36p 1635g SL 131
Super Pan Bco Ajonjoli 680g SP WON 100  
Pan Blanco Bimbo Rendidor 567g BIM 49973
Gansito ME 5p 250g MTA MLA 49860

Where I want to keep everything before the number but I also don't want the two uppercase letter word example: ME, BK . I'm using ^((\\D*).*?) [^AZ]{2,3}

The expected result should be

Tortillas Bolsa
Tortillinas
Bollos
Super Pan Bco Ajonjoli
Pan Blanco Bimbo Rendidor
Gansito

With the regex I'm using I'm still getting the two capital letter words Bollos BK and Gansito ME

Answer 1

Pre-compile a regex pattern with a lookahead (explained below) and employ regex.match inside a list comprehension:

>>> import re
>>> p = re.compile(r'\D+?(?=\s*([A-Z]{2})?\s*\d)')
>>> [p.match(x).group() for x in data]

[
 'Tortillas Bolsa',
 'Tortillinas',
 'Bollos',
 'Super Pan Bco Ajonjoli',
 'Pan Blanco Bimbo Rendidor',
 'Gansito'
]

Here, data is your list of strings.

Details

\D+?            # anything that isn't a digit (non-greedy)
(?=             # regex-lookahead
\s*             # zero or more wsp chars
([A-Z]{2})?     # two optional uppercase letters
\s*   
\d              # digit
)

---

In the event of any string not containing the pattern you're looking for, the list comprehension will error out (with an AttributeError), since re.match returns None in that instance. You can then employ a loop and test the value of re.match before extracting the matched portion.

matches = []
for x in data:
    m = p.match(x)
    if m:
        matches.append(m.group())

Or, if you want a placeholder None when there's no match:

matches = []
for x in data:
    matches.append(m.group() if m else None)

Answer 2

You may use the lookahead feature:

I_WANT        = '(.+?)' # This is what you want
I_DO_NOT_WANT = '\s(?:[0-9]|(?:[A-Z]{2,3}\s))' # Stop-patterns
RE = '{}(?={})'.format(I_WANT, I_DO_NOT_WANT) # Combine the parts

[re.findall(RE, x)[0] for x in test_strings]
#['Tortillas Bolsa', 'Tortillinas', 'Bollos', 'Super Pan Bco Ajonjoli',
# 'Pan Blanco Bimbo Rendidor', 'Gansito']

Answer 3

Supposing that:

• All the words you want to match in your capture group start with an uppercase letter
• The rest of each word contains only lowercase letters
• Words are separated by a single space

...you can use the following regular expressions:

1. Using Unicode character properties :

    ^((\\p{Lu}\\p{Ll}+ )+) 

   > Try this regex on regex101.

2. Without Unicode support:

    ^(([Az][az]+ )+) 

   > Try this regex on regex101.

Answer 4

I suggest splitting on the first two uppercase letter word or a digit and grab the first item:

r = re.compile(r'\b[A-Z]{2}\b|\d')
[r.split(item)[0].strip() for item in my_list]
# => ['Tortillas Bolsa', 'Tortillinas', 'Bollos', 'Super Pan Bco Ajonjoli', 'Pan Blanco Bimbo Rendidor', 'Gansito']

See the Python demo

Pattern details

• \\b[AZ]{2}\\b - a whole (since \\b are word boundaries) two uppercase ASCII letter word
• | - or
• \\d - a digit.

With .strip() , all trailing and leading whitespace will get trimmed.

A slight variation for a re.sub :

re.sub(r'\s*(?:\b[A-Z]{2}\b|\d).*', '', s)

See the regex demo

Details

• \\s* - 0+ whitespace chars
• (?:\\b[AZ]{2}\\b|\\d) - either a two uppercase letter word or a digit
• .* - the rest of the line.

Answer 5

My 2 cents

^.*?(?=\s[\d]|\s[A-Z]{2,})

https://regex101.com/r/7xD7DS/1/