A new built-in function, enumerate(), will make
certain loops a bit clearer. enumerate(thing), where
thing is either an iterator or a sequence, returns a iterator
that will return (0, thing[0]), (1,
thing[1]), (2, thing[2]), and so forth.
A common idiom to change every element of a list looks like this:
for i in range(len(L)):
item = L[i]
# ... compute some result based on item ...
L[i] = result
This can be rewritten using enumerate() as:
for i, item in enumerate(L):
# ... compute some result based on item ...
L[i] = result
See Also:
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