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Javascript: How to check if a string is empty? [duplicate]
I know this is really basic, but I am new to javascript and can't find an answer anywhere.
5 Answers
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How can I alter a primary key constraint using SQL syntax?
...rimary key constraint name, use query found here to look it up (or look up and drop all at once). http://stackoverflow.com/a/13948609/945875
– Justin
Dec 19 '13 at 20:06
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Check if value already exists within list of dictionaries?
...sing the above code can give you a KeyError. You can fix this by using get and providing a default value. If you don't provide a default value, None is returned.
if not any(d.get('main_color', default_value) == 'red' for d in a):
# does not exist
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How often does python flush to a file?
... to use the system default, which is usually line buffered for tty devices and fully buffered for other files.
If omitted, the system default is used.
code:
bufsize = 0
f = open('file.txt', 'w', buffering=bufsize)
shar...
Pandas: create two new columns in a dataframe with values calculated from a pre-existing column
I am working with the pandas library and I want to add two new columns to a dataframe df with n columns (n > 0).
These new columns result from the application of a function to one of the columns in the dataframe.
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How should I copy Strings in Java?
...e safe. The latter, however, is less efficient (it creates an extra object and in some cases copies the character data).
With this in mind, the first version should be preferred.
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improve th...
npm: disable postinstall script for package
...ch options? This is not described in 'npm help install', 'npm help config' and 'npm help scripts'.
– farwayer
May 6 '14 at 23:55
3
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How to correct indentation in IntelliJ
...ents, is there any way for auto-indent for comments. I want to format code and comments of the same way that eclipse does.
– dtrejogo
Jul 29 '14 at 19:45
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How do you use an identity file with rsync?
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You may want to use ssh-agent and ssh-add to load the key into memory. ssh will try identities from ssh-agent automatically if it can find them. Commands would be
eval $(ssh-agent) # Create agent and environment variables
ssh-add ~/.ssh/1234-identity
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How to Right-align flex item?
...e same thing in this case. The advantage would be having other properties (and behaviour) associated with flex items that the table approach doesn't have (flex, order, etc).
– adrift
Mar 16 '14 at 14:38
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