Elwin Estle wrote:
Tcl's list search command has the option to search for a list element
that matches a given regex. Is there something similar in python?
Not using regexes.
If not, it seems like it should be fairly trivial for me to write my
own (just wondering if I would be re-inventing the wheel).
If all you want to do is match an exact string, then lists already have
this:
>>> ['fe', 'fi', 'fo', 'fum'].index('fo')
2
If you want to match the start of the item:
def find_prefix(alist, prefix):
for i, item in enumerate(alist):
if item.startswith(prefix):
return i
raise ValueError('not found')
Or match a substring:
def find_substring(alist, substr):
for i, item in enumerate(alist):
if substr in item:
return i
raise ValueError('not found')
If all you want is *exact* matches, these will be much faster than a
regex solution. If you want case-insensitive exact matches:
def find_exact(alist, target, insensitive=False):
if insensitive:
return alist.index(target)
target = target.lower()
for i, item in enumerate(alist):
if item.lower() == target:
return i
raise ValueError('not found')
To match with a regex, something like this should work:
import re
def find_re(alist, prefix):
for i, item in enumerate(alist):
if re.search(prefix, item):
return i
raise ValueError('not found')
or use re.match to match a prefix instead.
--
Steven
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