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"Mutable and Immutable Types" example

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Assessment

Difficulty
1/5
Estimated time
Under an hour
Newbie friendliness
48/100
Issue type
Documentation
Clarity
Clearly specified
Activity status
Stale
Tech stack
python
Domain
documentation

Research direction

Start with the “Mutable and Immutable Types” section of the linked “Structuring Your Project” page and compare the existing example with the proposed expression. Done means the documentation uses the agreed example and presents any performance claim accurately.

Written by the indexing model from the issue text.

Description

The best example in the Mutable and Immutable Types section of the Structuring Your Project page is:

# create a concatenated string from 0 to 19 (e.g. "012..1819")
nums = [str(n) for n in range(20)]
print "".join(nums)

It is considered the best example for being both more efficient and succinct.

Would this be a better example to use?

''.join(map(str, range(20)))

It's more succinct and is faster:

$ python -m timeit "nums = [str(n) for n in range(20)]; ''.join(nums)"
100000 loops, best of 3: 6.84 usec per loop

$ python -m timeit "''.join(map(str, range(20)))"
100000 loops, best of 3: 4.93 usec per loop
Dominant language
Batchfile
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