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How to raise a ValueError?
...od named __contains__() that does something a little different, membership-testing-wise.
def contains(char_string, char):
largest_index = -1
for i, ch in enumerate(char_string):
if ch == char:
largest_index = i
if largest_index > -1: # any found?
return l...
What is the difference between `let` and `var` in swift?
...erence comes when using it with class instances (reference types):
class CTest
{
var str : String = ""
}
let letTest = CTest()
letTest.str = "test" // OK
letTest.str = "another test" // Still OK
//letTest = CTest() // Error
var varTest1 = CTest()
var varTest2 = CTest()
var varTest3 = CTest(...
Does Java have something like C#'s ref and out keywords?
...ing:
void changeString( _<String> str ) {
str.s("def");
}
void testRef() {
_<String> abc = new _<String>("abc");
changeString( abc );
out.println( abc ); // prints def
}
Out
void setString( _<String> ref ) {
str.s( "def" );
}
void testOut(){
_&...
PHP - add item to beginning of associative array [duplicate]
...
@melvin: Perhaps you could do a performance test and tell us.
– Vael Victus
Aug 20 '13 at 20:49
...
How do I break out of a loop in Scala?
...ral options.
(1a) Use some construct that includes a conditional that you test.
var sum = 0
(0 to 1000).iterator.takeWhile(_ => sum < 1000).foreach(i => sum+=i)
(warning--this depends on details of how the takeWhile test and the foreach are interleaved during evaluation, and probably sh...
What are attributes in .NET?
...out some and certain frameworks frameworks use some (e.g. NUnit looks for [TestFixture] on a class and [Test] on a test method when loading an assembly).
So when creating your own custom attribute be aware that it will not impact the behaviour of your code at all. You'll need to write the other part...
Can pandas automatically recognize dates?
...tions of date though. Apologies to pandas developers,here but i have not tested it with local dates recently.
you can use the date_parser parameter to pass a function to convert your format.
date_parser : function
Function to use for converting a sequence of string columns to an array of datetim...
What is the meaning of “this” in Java?
...ontext of an object. So if you have a class like this:
public class MyThisTest {
private int a;
public MyThisTest() {
this(42); // calls the other constructor
}
public MyThisTest(int a) {
this.a = a; // assigns the value of the parameter a to the field of the same name
}
publ...
CSS: How to position two elements on top of each other, without specifying a height?
... <div class="layer1">
<span>Lorem ipsum...<br>Test test</span>
</div>
<div class="layer2">
More lorem ipsum...
</div>
</div>
<div class="container_row">
...same HTML as above. This one should never overla...
How do I profile memory usage in Python?
...con', 1220), ('dis', 1002), ('pro', 809)]
Top 3 lines
#1: scratches/memory_test.py:37: 6527.1 KiB
words = list(words)
#2: scratches/memory_test.py:39: 247.7 KiB
prefix = word[:3]
#3: scratches/memory_test.py:40: 193.0 KiB
counts[prefix] += 1
4 other: 4.3 KiB
Total allocated size: 6972.1 ...