Comparison of Greedy and Sparse [python] ...
Regular Expressions - Extra Elements example from a Well House Consultants training course
More on Regular Expressions - Extra Elements [link]
Source code: lazyvgreedy.py Module: Q803
# As much as possible ...
greedy = re.compile (r'<(.*)>')
# However ... the "." does NOT match the new line character
# As little as possible ...
sparse = re.compile (r'<(.*?)>')
# As much as possible ...
pigginggreedy = re.compile (r'<(.*)>',re.DOTALL)
# Now ... the "." DOES match the new line character
info = ["<h1>Hello World<br />What a fun site</h1>\n<h4>Overview</h4>"]
for demo in info:
result = greedy.findall(demo)
print "GREEDY: ",result
result = sparse.findall(demo)
print "SPARSE: ",result
result = pigginggreedy.findall(demo)
print "MEGAGREEDY: ",result
wizard:pyoo graham$ python lazyvgreedy
GREEDY: ['h1>Hello World<br />What a fun site</h1', 'h4>Overview</h4']
SPARSE: ['h1', 'br /', '/h1', 'h4', '/h4']
MEGAGREEDY: ['h1>Hello World<br />What a fun site</h1>\n<h4>Overview</h4']
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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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