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How to count items in a Go map?
...le examples ported from the now-retired SO documentation:
m := map[string]int{}
len(m) // 0
m["foo"] = 1
len(m) // 1
If a variable points to a nil map, then len returns 0.
var m map[string]int
len(m) // 0
Excerpted from Maps - Counting map elements. The original author was Simone Carletti....
How to get unique values in an array
...t you have to use Array.from(... new Set(a)) since Set can't be implicitly converted to an array type. Just a heads up!
– Zachscs
Apr 27 '18 at 21:25
5
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Given a DateTime object, how do I get an ISO 8601 date in string format?
...e correct. FYI the formatexception's message is: "A UTC DateTime is being converted to text in a format that is only correct for local times. This can happen when calling DateTime.ToString using the 'z' format specifier, which will include a local time zone offset in the output."
...
How to create a custom attribute in C#
...that you understand what attributes are:
Attributes are metadata compiled into your program. Attributes themselves do not add any functionality to a class, property or module - just data. However, using reflection, one can leverage those attributes in order to create functionality.
So, for instanc...
Rounding up to next power of 2
... for a 32-bit value:
Round up to the next highest power of 2
unsigned int v; // compute the next highest power of 2 of 32-bit v
v--;
v |= v >> 1;
v |= v >> 2;
v |= v >> 4;
v |= v >> 8;
v |= v >> 16;
v++;
The extension to other widths should be obvious.
...
.NET Global exception handler in console application
...running. Catching those requires delaying the jitter, move the risky code into another method and apply the [MethodImpl(MethodImplOptions.NoInlining)] attribute to it.
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Recursion or Iteration?
...gorithms to make them faster and more efficient. He also goes over how to convert a traditional loop into a recursive function and the benefits of using tail-end recursion. His closing words really summed up some of my key points I think:
"recursive programming gives the programmer a better w...
How can I check if multiplying two numbers in Java will cause an overflow?
...
Java 8 has Math.multiplyExact, Math.addExact etc. for ints and long. These throw an unchecked ArithmeticException on overflow.
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What is the difference between `let` and `var` in swift?
...56329
EDIT
Because comments asking for adding other facts to the answer, converting this to community wiki answer. Feel free edit the answer to make it better.
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Function overloading in Javascript - Best practices
...ring p1) {return p1;}
public string CatStrings(string p1, int p2) {return p1+p2.ToString();}
public string CatStrings(string p1, int p2, bool p3) {return p1+p2.ToString()+p3.ToString();}
CatStrings("one"); // result = one
CatStrings("one",2); // result = one2
C...