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Create an empty object in JavaScript with {} or new Object()?
...can receive a parameter, and depending on that parameter, it will create a string, a number, or just an empty object.
For example: new Object(1), will return a Number. new Object("hello") will return a string, it means that the object constructor can delegate -depending on the parameter- the object...
Creating C macro with ## and __LINE__ (token concatenation with positioning macro)
...the token-pasting operator ## are applied to it. So, you have to use some extra layers of indirection, you can use the token-pasting operator with a recursively expanded argument:
#define TOKENPASTE(x, y) x ## y
#define TOKENPASTE2(x, y) TOKENPASTE(x, y)
#define UNIQUE static void TOKENPASTE2(Uniq...
Does Java support default parameter values?
...ys to simulate default parameters in Java:
Method overloading.
void foo(String a, Integer b) {
//...
}
void foo(String a) {
foo(a, 0); // here, 0 is a default value for b
}
foo("a", 2);
foo("a");
One of the limitations of this approach is that it doesn't work if you have two optional ...
What is the copy-and-swap idiom?
...
std::swap(this_string, that) doesn't provide a no-throw guarantee. It provides strong exception safety, but not a no-throw guarantee.
– wilhelmtell
Dec 22 '10 at 14:59
...
What does -D_XOPEN_SOURCE do/mean?
...t;some number>
it tells your compiler to include definitions for some extra functions that are defined in the X/Open and POSIX standards.
This will give you some extra functionality that exists on most recent UNIX/BSD/Linux systems, but probably doesn't exist on other systems such as Windows.
...
Check if a temporary table exists and delete if it exists before creating a temporary table
...the problem.
The following works fine for me in SQL Server 2005, with the extra "foo" column appearing in the second select result:
IF OBJECT_ID('tempdb..#Results') IS NOT NULL DROP TABLE #Results
GO
CREATE TABLE #Results ( Company CHAR(3), StepId TINYINT, FieldId TINYINT )
GO
select company, step...
Add alternating row color to SQL Server Reporting services report
...********************************
Function AlternateColor(ByVal OddColor As String, _
ByVal EvenColor As String, ByVal Toggle As Boolean) As String
If Toggle Then bOddRow = Not bOddRow
If bOddRow Then
Return OddColor
Else
Return EvenColor
End If
End Function
...
Git merge without auto commit
...t the ideal situation: fast-forwards are a Good Thing, and not having this extra "merge commit" Makes Sense. This is good default behavior and shouldn't be disabled. (In proper parlance, a fast-forward is a type of merge, but it isn't a "true merge".)
– michael
...
How Do I Choose Between a Hash Table and a Trie (Prefix Tree)?
...f hash table and trie have the same complexity on query, O(k) for k length string why should we go for hash? could you please explain?
– Sazzad Hissain Khan
Feb 12 '18 at 4:00
...
How to split a long regular expression into multiple lines in JavaScript?
...
You could convert it to a string and create the expression by calling new RegExp():
var myRE = new RegExp (['^(([^<>()[\]\\.,;:\\s@\"]+(\\.[^<>(),[\]\\.,;:\\s@\"]+)*)',
'|(\\".+\\"))@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\....