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What is a NullReferenceException, and how do I fix it?
... case:
string GetCategory(Book b)
{
if (b == null)
return "Unknown";
return b.Category;
}
Explicitly check for null from method calls and throw a custom exception.
You can also throw a custom exception, only to catch it in the calling code:
string GetCategory(string bookTitle)
{
...
How to prevent ifelse() from turning Date objects into numeric objects
...<- "Date"
str(dates)
At first this felt a little "hackish" to me. But now I just think of it as a small price to pay for the performance returns that I get from ifelse(). Plus it's still a lot more concise than a loop.
...
Difference between git stash pop and git stash apply
...ains "Hello" string.
Let's modify the file and add " world" string to it. Now you want to move to a different branch to fix a minor bug you've just found, so you need to stash your changes:
git stash
You moved to the other branch, fixed the bug and now you're ready to continue working on your ma...
What is a patch in git version control?
...TS)
See also Contributing to Rails with Git as another concrete example.
Nowadays, the GitHub pull request makes it really easy to apply patches on GitHub repos, which is useful when you aren't a direct contributor (ie you have no right to directly push to a repo).
Actually, fairly recently GitHub...
What is x after “x = x++”?
...
I know this is super old, but I have a question. Is the above order of operation guaranteed by the standard? Is it possible that the assignment is executed before the increment?
– Emerald Weapon
...
Check for column name in a SqlDataReader object
...he loop doesn't. It is, however, a completely hypothetical situation right now so it's a very flimsy justification. Regardless, bear with me and see what you think.
Imagine a database that allowed you to "alias" columns within a table. Imagine that I could define a table with a column called "Emplo...
Javascript AES encryption [closed]
...
This is now quite useful and feature rich code.google.com/p/crypto-js
– David Kierans
Apr 25 '12 at 4:21
2
...
jQuery AJAX cross domain
...
It's 2016. CORS is now a widely supported standard, as opposed to JSONP which can only be described as a hack. @joshuarh's answer below should be the preferred one now.
– Vicky Chijwani
Jul 20 '16 at 9:16
...
Git commit with no commit message
...essages that I have written that will never ever be read by anyone. For me now the value of this habit is that it forces me to look through the changes in an attempt to describe them, and this sometimes makes me notice bugs. You are right, though. I'll consider paying more attention to the code and ...
What is the Python equivalent of Matlab's tic and toc functions?
...TicToc, marks the beginning of a time interval
toc(False)
That's it! Now we are ready to fully use tic() and toc() just as in Matlab. For example
tic()
time.sleep(5)
toc() # returns "Elapsed time: 5.00 seconds."
Actually, this is more versatile than the built-in Matlab functions. Here, ...