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Proper MIME media type for PDF files
When working with PDFs, I've run across the MIME types application/pdf and application/x-pdf among others.
3 Answers
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Break promise chain and call a function based on the step in the chain where it is broken (rejected)
...et's say you have something like the following:
stepOne()
.then(stepTwo, handleErrorOne)
.then(stepThree, handleErrorTwo)
.then(null, handleErrorThree);
To better understand what's happening, let's pretend this is synchronous code with try/catch blocks:
try {
try {
try {
...
How do I redirect in expressjs while passing some context?
...gs. You'll need to ensure that the values are properly encodeURIComponent and decodeURIComponent.
app.get('/category', function(req, res) {
var string = encodeURIComponent('something that would break');
res.redirect('/?valid=' + string);
});
You can snag that in your other route by getting t...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable icc , will eliminate the library call for pow(a,6) .)
...
Optimal number of threads per core
Let's say I have a 4-core CPU, and I want to run some process in the minimum amount of time. The process is ideally parallelizable, so I can run chunks of it on an infinite number of threads and each thread takes the same amount of time.
...
How do I check if a string contains another string in Objective-C?
...");
}
The key is noticing that rangeOfString: returns an NSRange struct, and the documentation says that it returns the struct {NSNotFound, 0} if the "haystack" does not contain the "needle".
And if you're on iOS 8 or OS X Yosemite, you can now do: (*NOTE: This WILL crash your app if this code ...
Why are arrays of references illegal?
...
Answering to your question about standard I can cite the C++ Standard §8.3.2/4:
There shall be no references to references, no arrays of references, and no pointers to references.
...
Can we instantiate an abstract class?
... are creating an instance of an anonymous subclass of your abstract class. And then you are invoking the method on your abstract class reference pointing to subclass object.
This behaviour is clearly listed in JLS - Section # 15.9.1: -
If the class instance creation expression ends in a class b...
Sort JavaScript object by key
...swers to this question are outdated, never matched implementation reality, and have officially become incorrect now that the ES6/ES2015 spec has been published.
See the section on property iteration order in Exploring ES6 by Axel Rauschmayer:
All methods that iterate over property keys do so ...
What is the fastest way to get the value of π?
... fastest π I know of is the one with the digits hard coded. Looking at Pi and Pi[PDF], there are a lot of formulae.
Here is a method that converges quickly — about 14 digits per iteration. PiFast, the current fastest application, uses this formula with the FFT. I'll just write the formula, since...