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Is it better to call ToList() or ToArray() in LINQ queries?
...lare it. This is usually because I need to iterate over it multiple times and it is expensive to compute. For example:
16...
Usage of protocols as array types and function parameters in swift
.... Such protocols use Self or associatedtype keywords in their definitions (and Equatable is one of them).
In some cases it's possible to use a type-erased wrapper to make your collection homomorphic. Below is an example.
// This protocol doesn't provide polymorphism over the types which implement ...
Why is transposing a matrix of 512x512 much slower than transposing a matrix of 513x513?
...
The explanation comes from Agner Fog in Optimizing software in C++ and it reduces to how data is accessed and stored in the cache.
For terms and detailed info, see the wiki entry on caching, I'm gonna narrow it down here.
A cache is organized in sets and lines. At a time, only one set is u...
Commit only part of a file in Git
...nted by lines beginning with "-". You can prevent staging their removal by converting the "-" to a " " (space).
modified content:
Modified content is represented by "-" lines (removing the old content) followed by "+" lines (adding the replacement content). You can prevent staging the modifica...
Is there a performance difference between a for loop and a for-each loop?
... The for-each loop, introduced in
release 1.5, gets rid of the clutter
and the opportunity for error by
hiding the iterator or index variable
completely. The resulting idiom
applies equally to collections and
arrays:
// The preferred idiom for iterating over collections and arrays
for (...
Node.js throws “btoa is not defined” error
...mmatic interface, it only provides command line utilities.
If you need to convert to Base64 you could do so using Buffer:
console.log(Buffer.from('Hello World!').toString('base64'));
Reverse (assuming the content you're decoding is a utf8 string):
console.log(Buffer.from(b64Encoded, 'base64').t...
Setting Short Value Java
... There are suffixes for other types as well: d/D makes a double and f/F makes a float!
– Joachim Sauer
Feb 19 '10 at 8:48
6
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What is the best way to give a C# auto-property an initial value?
...
In C# 5 and earlier, to give auto implemented properties an initial value, you have to do it in a constructor.
Since C# 6.0, you can specify initial value in-line. The syntax is:
public int X { get; set; } = x; // C# 6 or higher
...
Can I “multiply” a string (in C#)?
...
And it's not much more in .NET 3.5: String.Concat(Enumerable.Repeat("Hello", 4).ToArray())
– Mark Foreman
Sep 3 '12 at 0:54
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Last iteration of enhanced for loop in java
...e don't use "" + i, by the way - you don't really want concatenation here, and StringBuilder has a perfectly good append(int) overload.)
int[] array = {1, 2, 3...};
StringBuilder builder = new StringBuilder();
for (int i : array) {
if (builder.length() != 0) {
builder.append(",");
...