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JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
a "problem" which i have every now and then is that i have an object e.g. user = {} and through the course of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
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Update a record without first querying?
Lets say I query the database and load a list of items. Then I open one of the items in a detail view form, and instead of re-querying the item out of the database, I create an instance of the item from the datasource in the list.
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Openssl is not recognized as an internal or external command
...integrated with Facebook. In one of Facebook's tutorials, I found this command:
15 Answers
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Keyboard shortcut to paste clipboard content into command prompt window (Win XP) [closed]
...re a keyboard shortcut for pasting the content of the clipboard into a command prompt window on Windows XP (instead of using the right mouse button)?
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Cron job every three days
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This is a very high result on google, and as such it would be better if the accepted answer was correct, which this is not. I believe Tareco's explanation is correct.
– lynks
Sep 4 '12 at 14:21
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ProcessStartInfo hanging on “WaitForExit”? Why?
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The problem is that if you redirect StandardOutput and/or StandardError the internal buffer can become full. Whatever order you use, there can be a problem:
If you wait for the process to exit before reading StandardOutput the process can block trying to write ...
What's the difference between lists enclosed by square brackets and parentheses in Python?
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for the above 'y=x' example , list and tuple behave in the same way now (verified in python3.8.5)
– Youjun Hu
Aug 15 at 9:11
add a comm...
How do I make an HTTP request in Swift?
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You can use URL, URLRequest and URLSession or NSURLConnection as you'd normally do in Objective-C. Note that for iOS 7.0 and later, URLSession is preferred.
Using URLSession
Initialize a URL object and a URLSessionDataTask from URLSession. Then run the ...
Using smart pointers for class members
I'm having trouble understanding the usage of smart pointers as class members in C++11. I have read a lot about smart pointers and I think I do understand how unique_ptr and shared_ptr / weak_ptr work in general. What I don't understand is the real usage. It seems like everybody recommends using...
Finding what methods a Python object has
...t an AttributeError, you can use this instead:
getattr( is intolerant of pandas style python3.6 abstract virtual sub-classes. This code does the same as above and ignores exceptions.
import pandas as pd
df = pd.DataFrame([[10, 20, 30], [100, 200, 300]],
columns=['foo', 'bar',...