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Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?
Is there a better way than the following to check to see if a string is nil OR has a length of 0 in Ruby?
16 Answers
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setBackground vs setBackgroundDrawable (Android)
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It's deprecated but it still works so you could just use it. But if you want to be completly correct, just for the completeness of it... You'd do something like following:
int sdk = android.os.Build.VERSION.SDK_INT;
if(sdk < android.os.Build.VERSION_CODES.JELLY_BEAN) {
setBackgroun...
How to revert initial git commit?
...tial commit, but keeps all previously commited changes added to the index. If you want to also remove those changes, just execute a following git reset --hard. Even if incomplete, this answer is indeed the best one, so avoid using rm -fr .git (unless you know what you are doing).
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Appropriate datatype for holding percent values?
..., the data type you use depends on how you plan to store your percentages. If you are going to store their fractional equivalent (e.g. 100.00% stored as 1.0000), I would store the data in a decimal(5,4) data type with a CHECK constraint that ensures that the values never exceed 1.0000 (assuming that...
gcc warning" 'will be initialized after'
I am getting a lot of these warnings from 3rd party code that I cannot modify.
Is there a way to disable this warning or at least disable it for certain areas (like #pragma push/pop in VC++)?
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Python json.loads shows ValueError: Extra data
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ValueError: Extra data: line 1 column 3 - line 1 column 5 (char 2 - 4)
If you want to dump multiple dictionaries, wrap them in a list, dump the list (instead of dumping dictionaries multiple times)
>>> dict1 = {}
>>> dict2 = {}
>>> json.dumps([dict1, dict2])
'[{}, {}]...
Vagrant's port forwarding not working [closed]
...omments.
First thing: try curl 'http://localhost:80' from within the VM. If that doesn't work, then it's definitely not the port forwarding.
Next: try curl -v 'http://localhost:4567/' from your host machine. Curl might give you a better error message than Safari.
I'd check that there are no fir...
What is the difference between sites-enabled and sites-available directory?
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The difference is that virtual sites listed in the sites-enabled directory are served by apache. In the sites-available directory there are the virtual sites that exist on your server but people can't access them because they are ...
Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...code (full compiler optimizations), and switching from iostreams to OS-specific I/O APIs and custom buffer management does give an order of magnitude improvement.
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Maximum packet size for a TCP connection
...ld use a lower one. With the advent of jumbo frames, there is no real specified maximum, and the maximum varies depending on the hardware and driver.
– WhirlWind
Apr 10 '10 at 17:08
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