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difference between foldLeft and reduceLeft in Scala
I have learned the basic difference between foldLeft and reduceLeft
7 Answers
7
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Structs in Javascript
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The only difference between object literals and constructed objects are the properties inherited from the prototype.
var o = {
'a': 3, 'b': 4,
'doStuff': function() {
alert(this.a + this.b);
}
};
o.doStuff(); // displays: 7
...
How to set environment variables in Jenkins?
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EnvInject does not work if the "execute shell" exits with an error because the build does not proceed to the injection part.
– Chadi
Apr 19 '16 at 7:57
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Why does `a == b or c or d` always evaluate to True?
...integer as True.
In [11]: if 3:
...: print ("yey")
...:
yey
Now, Python builds on that logic and let you use logic literals such as or on integers, and so
In [9]: False or 3
Out[9]: 3
Finally
In [4]: a==b or c or d
Out[4]: 3
The proper way to write it would be:
In [13]: if a i...
What characters are allowed in DOM IDs? [duplicate]
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Actually there is a difference between HTML and XHTML.
As XHTML is XML the rules for XML IDs apply:
Values of type ID MUST match the Name production.
NameStartChar ::= ":" | [A-Z] | "_" | [a-z] | [#xC0-#xD6] |
[#xD8-...
Create subdomains on the fly with .htaccess (PHP)
...DNS server *.website.com
Then in your vhost container you will need to specify the wildcard as well *.website.com - This is done in the ServerAlias DOCs
Then extract and verify the subdomain in PHP and display the appropriate data
The long version
1. Create a wildcard DNS entry
In your DNS setti...
What is the performance of Objects/Arrays in JavaScript? (specifically for Google V8)
...;
var lastLongI = 1;
for(var i=0;i<10000;i++)
{
var before = Date.now();
for(var j=0;j<arrayCount;j++)
dynamicArrays[j][i] = i;
var span = Date.now() - before;
if (span > 10)
{
console.log(i + ": " + span + "ms" + " " + (i / lastLongI));
lastLongI =...
List of Big-O for PHP functions
After using PHP for a while now, I've noticed that not all built-in PHP functions are as fast as expected. Consider these two possible implementations of a function that finds if a number is prime using a cached array of primes.
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Make sure only a single instance of a program is running
...tendo import singleton
me = singleton.SingleInstance() # will sys.exit(-1) if other instance is running
The latest code version is available singleton.py. Please file bugs here.
You can install tend using one of the following methods:
easy_install tendo
pip install tendo
manually by getting it ...
How is this fibonacci-function memoized?
...!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
That is what that trick, "going-through-a-list", is exploiting. In normal doubly-recursve Fibonacci definition, fib n = fib (n-1) + fib (n-2), the function itself gets called, twice from the top,...