Most elegant way to check if the string is empty in Python?
Does Python have something like an empty string variable where you can do?:
if myString == string.empty:
Regardless what's the most elegant way to check for empty string values? I find hard coding "" every time for checking an empty string not as good.
Empty strings are "falsy" which means they are considered false in a Boolean context, so you can just do this:
if not myString:
This is the preferred way if you know that your variable is a string. If your variable could also be some other type then you should use myString == "" . See the documentation on Truth Value Testing for other values that are false in Boolean contexts.
From PEP 8, in the “Programming Recommendations” section:
For sequences, (strings, lists, tuples), use the fact that empty sequences are false.
So you should use:
if not some_string:
or:
if some_string:
Just to clarify, sequences are evaluated to False or True in a Boolean context if they are empty or not. They are not equal to False or True .
The most elegant way would probably be to simply check if its true or falsy, eg:
if not my_string:
However, you may want to strip white space because:
>>> bool("")
False
>>> bool(" ")
True
>>> bool(" ".strip())
False
You should probably be a bit more explicit in this however, unless you know for sure that this string has passed some kind of validation and is a string that can be tested this way.
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