Negative lookahead - does not consume / must fail to match [Python]
Regular Expressions - Extra Elements example from a Well House Consultants training course
More on Regular Expressions - Extra Elements [link]
Source code: lookahead.py Module: Q803
# Looking for .....ing?on EXCEPT ington !
samevalues = re.compile (r'(\w+)(?!ington)ing\won')
# You may find this easier ;-)
#samevalues = re.compile (r'(\w+)ing[a-su-z]on')
info = ["Hello Orpington, Blessington, Huntingdon"]
for demo in info:
result = samevalues.findall(demo)
print demo, "YES"
print demo, "NO"
wizard:pyoo graham$ python lookahead
Hello Orpington, Blessington, Huntingdon YES
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This example comes from our "Regular Expressions - Extra Elements" training module. You'll find a description of the topic and some other closely related examples on the "Regular Expressions - Extra Elements" module index page.
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