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What is the >>>= operator in C?
...s a boolean it's true, so 0xFULL ? '\0' : -1 evaluates to '\0', which is a character literal whose numerical value is simply 0.
Meanwhile, 0X.1P1 is a hexadecimal floating point literal equal to 2/16 = 0.125. In any case, being non-zero, it's also true as a boolean, so negating it twice with !! ag...
What's the difference between django OneToOneField and ForeignKey?
...Guide to Django:
OneToOneField
A one-to-one relationship. Conceptually, this is similar to a ForeignKey with unique=True, but the "reverse" side of the relation will directly return a single object.
In contrast to the OneToOneField "reverse" relation, a ForeignKey "reverse" relation retur...
How to list all installed packages and their versions in Python?
Is there a way in Python to list all installed packages and their versions?
11 Answers
...
std::function and std::bind: what are they, and when should they be used?
...nd to get g:
auto g = bind(f, _1, 4, _2);
This is more concise than actually writing a functor class to do it.
There are further examples in the article you link to. You generally use it when you need to pass a functor to some algorithm. You have a function or functor that almost does the job yo...
How to print a number with commas as thousands separators in JavaScript
...urpose. Here is what I did:
function numberWithCommas(x) {
return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
}
function numberWithCommas(x) {
return x.toString().replace(/\B(?<!\.\d*)(?=(\d{3})+(?!\d))/g, ",");
}
function test(x, expect) {
const result = numberWi...
Is there a TRY CATCH command in Bash
... writing a shell script and need to check that a terminal app has been installed. I want to use a TRY/CATCH command to do this unless there is a neater way.
...
Count how many files in directory PHP
...n you include other directories within that directories and so on to count all files and exclude directories from the count?
– The Bumpaster
Jul 2 '16 at 13:40
1
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How to add an Access-Control-Allow-Origin header
...ame" https://auth.api.rackspacecloud.com/v1.0
From the results returned, extract the values for X-Auth-Token and X-Storage-Url
curl -X POST \
-H "Content-Type: font/woff" \
--header "X-Auth-Token: returned-x-auth-token" returned-x-storage-url/name-of-your-container/fonts/fontawesome-webfont.w...
How to wait for a keypress in R?
...
This answer is similar to that of Simon's, but does not require extra input other than a newline.
cat("Press Enter to continue...")
invisible(scan("stdin", character(), nlines = 1, quiet = TRUE))
Using nlines=1 instead of n=1, the user can simply press enter to continue the Rscript.
...
How do you run your own code alongside Tkinter's event loop?
...tion for the after method:
def after(self, ms, func=None, *args):
"""Call function once after given time.
MS specifies the time in milliseconds. FUNC gives the
function which shall be called. Additional parameters
are given as parameters to the function call. Return
identifier...