python – How to check if the string is empty?

python – How to check if the string is empty?

Empty strings are falsy (python 2 or python 3 reference), 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 ‚ÄúProgramming Recommendations‚ÄĚ 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.

python – How to check if the string is empty?

The most elegant way would probably be to simply check if its true or falsy, e.g.:

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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